Cut Emissions Food, Agriculture, Land & Ocean (FALO) Shift Agriculture Practices

Improve Rice Production

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Rice field

Rice production is a significant source of methane emissions and a minor source of nitrous oxide emissions. Most rice production occurs in flooded fields called paddies, where anaerobic conditions trigger high levels of methane production. This solution includes two related practices that each reduce emissions from paddy rice production: noncontinuous flooding and nutrient management. Noncontinuous flooding is a water management technique that reduces the amount of time rice paddy soils spend fully saturated, thereby reducing methane. Unfortunately, noncontinuous flooding increases nitrous oxide emissions. Nutrient management helps to address this challenge by controlling the timing, amount, and type of fertilization to maximize plant uptake and minimize nitrous oxide emissions.

Last updated September 23, 2025

Solution Basics

ha rice paddies

t CO₂-eq (100-yr)/unit/yr
2.03
units
Current 4.865×10⁷ 04.956×10⁷7.753×10⁷
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.1 0.10.16
US$ per t CO₂-eq
-175
Emergency Brake

CH₄ , N₂O

Additional Benefits

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191,192,193

Overview

Rice is a staple crop of critical importance, occupying 11% of global cropland (FAOstat 2025). Rice production has higher GHG emissions than most crop production, accounting for 9% of all anthropogenic methane and 10% of cropland nitrous oxide (Wang et al., 2020). Nabuurs et al. (2022) found methane emissions from global rice production to be 0.8–1.0 Gt CO₂‑eq/yr and growing 0.4% annually.

Rice paddy systems are fields with berms and plumbing to permit the flooding of rice for the production periods, which helps with weed and pest control (rice thrives in flooded conditions, though it does not require them). Paddy rice is the main source of methane from rice production. Upland rice is grown outside of paddies and does not produce significant methane emissions, so we excluded it from this analysis. Irrigated paddies are provided with irrigation water, while rain-fed paddies are only filled by rainfall and runoff (Raffa, 2021). For this analysis, we considered both irrigated and rain-fed paddies.

Methane Reduction

Flooded rice paddies encourage the production of methane by microbes. Conventional paddy rice production uses continuous flooding, in which the paddy is flooded for the full rice production period. Several approaches can reduce methane, with the most widespread being noncontinuous flooding. This is a collection of practices (such as alternate wetting and drying) that drain the fields one or more times during the rice production period. As a result, the paddy spends less time in its methane-producing state. This can be done without reducing rice yields in many, but not all, cases, and also significantly reduces irrigation water use (Bo et al., 2022). Impacts on yields depend on soils, climate, and other variables (Cheng et al., 2022). 

Nitrous Oxide Reduction

A major drawback to noncontinuous flooding is that it increases nitrous oxide emissions from fertilizer compared to continuous flooding. High nitrogen levels in flooded paddies encourage the growth of bacteria that produce methane, reduce the natural breakdown of methane, and facilitate emissions of nitrous oxide to the atmosphere (Li et al., 2024). The effect is small compared to the mitigated emissions from methane reduction (Jiang et al., 2019), but remains serious. Use of nutrient management techniques, such as controlling fertilizer amount, type (e.g., controlled-release urea), timing, and application techniques (e.g., deep fertilization), can reduce these emissions. This is in part because nitrogen fertilizers are often overapplied, leaving room to increase efficiency without reducing rice yields (Hergoualc’h et al., 2019; Li et al., 2024). 

Other Promising Practices

Other practices also show potential but were not included in our analysis. These include the application of biochar to rice paddies and the use of rice cultivars that produce fewer emissions (Qian et al., 2023). Other approaches include saturated soil culture, System of Rice Intensification (“SRI”), ground-cover systems, raised beds, and improved irrigation and paddy infrastructure (Surendran et al., 2021). 

Note that some practices, such as incorporating rice straw or the use of compost or manure, can increase nitrous oxide emissions (Li et al., 2024). 

There is also evidence that, under some circumstances, noncontinuous flooding can sequester soil organic carbon by increasing soil organic matter. However, there are not enough data available to quantify this (Qian et al., 2023). Indeed, one meta-analysis found that noncontinuous flooding can actually lead to a decrease in soil organic carbon (Livsey et al., 2019). One complication is that many production areas plant rice two or even three times per year, and data are typically presented on a per-harvest or even per-flooded day basis. To overcome this challenge, we use data on the percentage of global irrigated rice land in single, double, and triple cropping from Carlson et al. (2016) to create weighted average values as appropriate.

Impact Calculator

Adjust effectiveness and adoption using range sliders to see resulting climate impact potential.

Effectiveness

2.03
t CO2-eq/ha/yr

Adoption

4.865×10⁷
ha rice paddies
Low
4.956×10⁷
High
7.753×10⁷
4.865×10⁷
current
Achievable Range

Climate Impact

0.10
Gt CO₂-eq/yr (100-yr)
05
which is the equivalent of
0.17%
of global emissions

Maps

Improved rice production has its greatest potential in regions where there is substantial paddy rice production and adequate water availability to allow farmers to implement drain/flood cycles throughout the growing season (noncontinuous flooding). Rice production is dominated by Asia, so the greatest potential for solution uptake is there. Brazil and the United States rank 9th and 11th for rice production, and each has regions where this solution would have multiple benefits. Because improved rice production solution may not decrease yields, not all paddy rice-growing areas are suitable. There are regions of great potential throughout Southeast Asia, particularly in Vietnam and Thailand.

Other factors besides biophysical factors govern the suitability of noncontinuous flooding. For example, farmers are more likely to release water in their fields if they are confident that water will be available for subsequent irrigation, which often depends on community structures. 

There is very scarce information on adoption of noncontinuous flooding, although Bangladesh, China, Japan, and South Korea have relatively high uptake.

% of area
0100

Paddy rice area, 2020

Rice is the third most widely grown crop in terms of cultivated area and provides more calories directly to people than any other crop. It also is an important source of methane emissions. Here we show pixels in which at least 1% of the area is devoted to paddy (flooded) rice. Upland (unflooded) rice is included in the Improve Nutrient Management solution.

Cao, P., Bilotto, F., Gonzalez Fischer, C., Mueller, N. D., Carlson, K. M., Gerber, J.S., Smith, P., Tubiello, F. N., West, P. C., You, L., & Herrero, M. (2025). Mapping greenhouse gas emissions from global cropland circa 2020 [Data set, PREPRINT Version 1]. In review at Nature Climate Change. Link to source: https://doi.org/10.21203/rs.3.rs-6622054/v1 

Tang, F. H. M., Nguyen, T. H., Conchedda, G., Casse, L., Tubiello, F. N., & Maggi, F. (2024). CROPGRIDS: A global geo-referenced dataset of 173 crops [Data set]. Scientific Data, 11(1), 413. Link to source: https://doi.org/10.1038/s41597-024-03247-7

% of area
0100

Paddy rice area, 2020

Rice is the third most widely grown crop in terms of cultivated area and provides more calories directly to people than any other crop. It also is an important source of methane emissions. Here we show pixels in which at least 1% of the area is devoted to paddy (flooded) rice. Upland (unflooded) rice is included in the Improve Nutrient Management solution.

Cao, P., Bilotto, F., Gonzalez Fischer, C., Mueller, N. D., Carlson, K. M., Gerber, J.S., Smith, P., Tubiello, F. N., West, P. C., You, L., & Herrero, M. (2025). Mapping greenhouse gas emissions from global cropland circa 2020 [Data set, PREPRINT Version 1]. In review at Nature Climate Change. Link to source: https://doi.org/10.21203/rs.3.rs-6622054/v1 

Tang, F. H. M., Nguyen, T. H., Conchedda, G., Casse, L., Tubiello, F. N., & Maggi, F. (2024). CROPGRIDS: A global geo-referenced dataset of 173 crops [Data set]. Scientific Data, 11(1), 413. Link to source: https://doi.org/10.1038/s41597-024-03247-7

The Details

Current State

Methane Reduction

We calculated per-hectare methane emissions using Intergovernmental Panel on Climate Change (IPCC) methodology (Ogle et. al, 2019). To develop regional emissions per rice harvest, we multiplied standard regional daily baseline emissions by standard cultivation period lengths, then multiplied by the mean scaling factor for noncontinuous flooding systems. However, the total number of rice harvests per year ranged from one to three. Carlson et al. (2016) reported a global figure of harvests on rice fields: 42% were harvested once, 50% were harvested twice, and 8% were harvested three times. We used this to develop a weighted average methane emissions figure for each region. National effectiveness ranged from 1.55 to 3.29 t CO₂‑eq /ha/yr (Table 1a).

Nitrous Oxide Reduction

Using data from Adalibieke et al. (2024) and Gerber et al. (2024), we calculated the current country-level rate of nitrogen application per hectare and a target rate reflecting improved efficiency through nutrient management. For a full methodology, see the Appendix. 

In noncontinuously flooded systems, nitrous oxide emissions are 1.66 times higher per t of nitrogen applied (Hergoualc’h et al., 2019). Using the different emissions factors, we calculated total nitrous oxide emissions for 1) flooded rice with current nitrogen application rates, and 2) noncontinuously flooded rice with target nitrogen application rates. 

The effectiveness of nutrient management for each country with over 100,000 ha of rice production ranged from –0.48 to 0.11 t CO₂‑eq /ha/yr (Table 1).

Combined Reduction

Combined effectiveness of methane and nitrous oxide reduction was 1.49–3.39 t CO₂‑eq /ha/yr (Table 1).

Table 1a. Combined effectiveness at reducing emissions, by country, for noncontinuous flooding with nutrient management. 

Unit: t CO₂‑eq /ha/yr

Afghanistan 1.63
Argentina 2.70
Bangladesh 1.63
Benin 2.30
Bolivia (Plurinational State of) 2.70
Brazil 2.70
Burkina Faso 2.30
Cambodia 2.13
Cameroon 2.30
Chad 2.30
China 2.48
Colombia 2.70
Côte d'Ivoire 2.30
Democratic People's Republic of Korea 2.48
Democratic Republic of the Congo 2.30
Dominican Republic 2.70
Ecuador 2.70
Egypt 2.30
Ghana 2.30
Guinea 2.30
Guinea-Bissau 2.30
Guyana 2.70
India 1.63
Indonesia 2.13
Iran (Islamic Republic of) 3.29
Italy 3.29
Japan 2.48
Lao People's Democratic Republic 2.13
Liberia 2.30
Madagascar 2.30
Malaysia 2.13
Mali 2.30
Mozambique 2.30
Myanmar 2.13
Nepal 1.63
Nigeria 2.30
Pakistan 1.63
Paraguay 2.70
Peru 2.70
Philippines 2.13
Republic of Korea 2.48
Russian Federation 3.29
Senegal 2.30
Sierra Leone 2.30
Sri Lanka 1.63
Thailand 2.13
Turkey 3.29
Uganda 2.70
United Republic of Tanzania 2.30
United States of America 1.55
Uruguay 2.70
Venezuela (Bolivarian Republic of) 2.70
Vietnam 2.13

Unit: t CO₂‑eq /ha/yr

Afghanistan 0.03
Argentina 0.07
Bangladesh 0.06
Benin 0.03
Bolivia (Plurinational State of) 0.00
Brazil 0.00
Burkina Faso –0.02
Cambodia 0.01
Cameroon 0.00
Chad 0.01
China 0.01
Colombia –0.07
Côte d'Ivoire 0.02
Democratic People's Republic of Korea 0.02
Democratic Republic of the Congo 0.01
Dominican Republic –0.16
Ecuador –0.08
Egypt –0.15
Ghana 0.05
Guinea 0.01
Guinea-Bissau 0.01
Guyana –0.06
India –0.02
Indonesia 0.11
Iran (Islamic Republic of) –0.05
Italy 0.00
Japan 0.07
Lao People's Democratic Republic 0.02
Liberia 0.02
Madagascar 0.00
Malaysia –0.01
Mali –0.03
Mozambique 0.01
Myanmar 0.04
Nepal 0.04
Nigeria 0.01
Pakistan –0.04
Paraguay 0.01
Peru 0.09
Philippines 0.00
Republic of Korea 0.00
Russian Federation 0.04
Senegal –0.04
Sierra Leone 0.02
Sri Lanka 0.02
Thailand –0.03
Turkey 0.10
Uganda 0.00
United Republic of Tanzania 0.04
United States of America –0.05
Uruguay 0.03
Venezuela (Bolivarian Republic of) –0.48
Vietnam 0.00

Unit: t CO₂‑eq /ha rice paddies/yr

Afghanistan 1.67
Argentina 2.77
Bangladesh 1.69
Benin 2.34
Bolivia (Plurinational State of) 2.70
Brazil 2.70
Burkina Faso 2.28
Cambodia 2.15
Cameroon 2.30
Chad 2.32
China 2.48
Colombia 2.63
Côte d'Ivoire 2.32
Democratic People's Republic of Korea 2.50
Democratic Republic of the Congo 2.31
Dominican Republic 2.54
Ecuador 2.62
Egypt 2.16
Ghana 2.35
Guinea 2.32
Guinea-Bissau 2.32
Guyana 2.63
India 1.61
Indonesia 2.24
Iran (Islamic Republic of) 3.24
Italy 3.29
Japan 2.54
Lao People's Democratic Republic 2.15
Liberia 2.32
Madagascar 2.31
Malaysia 2.13
Mali 2.28
Mozambique 2.32
Myanmar 2.17
Nepal 1.67
Nigeria 2.32
Pakistan 1.59
Paraguay 2.71
Peru 2.79
Philippines 2.14
Republic of Korea 2.47
Russian Federation 3.33
Senegal 2.27
Sierra Leone 2.32
Sri Lanka 1.65
Thailand 2.10
Turkey 3.39
Uganda 2.31
United Republic of Tanzania 2.35
United States of America 1.49
Uruguay 2.72
Venezuela (Bolivarian Republic of) 2.22
Vietnam 2.13

Table 1b. Combined effectiveness at reducing emissions, by country, for noncontinuous flooding with nutrient management. 

Unit: t CO₂‑eq /ha rice paddies/yr

Afghanistan 4.75
Argentina 7.85
Bangladesh 4.75
Benin 6.71
Bolivia (Plurinational State of) 7.85
Brazil 7.85
Burkina Faso 6.71
Cambodia 6.21
Cameroon 6.71
Chad 6.71
China 7.20
Colombia 7.85
Côte d'Ivoire 6.71
Democratic People's Republic of Korea 7.20
Democratic Republic of the Congo 6.71
Dominican Republic 7.85
Ecuador 7.85
Egypt 6.71
Ghana 6.71
Guinea 6.71
Guinea-Bissau 6.71
Guyana 7.85
India 4.75
Indonesia 6.21
Iran (Islamic Republic of) 9.57
Italy 9.57
Japan 7.20
Lao People's Democratic Republic 6.21
Liberia 6.71
Madagascar 6.71
Malaysia 6.21
Mali 6.71
Mozambique 6.71
Myanmar 6.21
Nepal 4.75
Nigeria 6.71
Pakistan 4.75
Paraguay 7.85
Peru 7.85
Philippines 6.21
Republic of Korea 7.20
Russian Federation 9.57
Senegal 6.71
Sierra Leone 6.71
Sri Lanka 4.75
Thailand 6.21
Turkey 9.57
Uganda 6.71
United Republic of Tanzania 6.71
United States of America 4.51
Uruguay 7.85
Venezuela (Bolivarian Republic of) 7.85
Vietnam 6.21

Unit: t CO₂‑eq /ha rice paddies/yr

Afghanistan 0.03
Argentina 0.07
Bangladesh 0.06
Benin 0.03
Bolivia (Plurinational State of) 0.00
Brazil 0.00
Burkina Faso 0.02
Cambodia 0.01
Cameroon 0.00
Chad 0.01
China 0.01
Colombia –0.07
Côte d'Ivoire 0.02
Democratic People's Republic of Korea 0.02
Democratic Republic of the Congo 0.01
Dominican Republic 0.16
Ecuador –0.08
Egypt –0.15
Ghana 0.05
Guinea 0.01
Guinea-Bissau 0.01
Guyana –0.06
India –0.02
Indonesia 0.11
Iran (Islamic Republic of) –0.05
Italy 0.00
Japan 0.07
Lao People's Democratic Republic 0.02
Liberia 0.02
Madagascar 0.00
Malaysia –0.01
Mali –0.03
Mozambique 0.01
Myanmar 0.04
Nepal 0.04
Nigeria 0.01
Pakistan –0.04
Paraguay 0.01
Peru 0.09
Philippines 0.00
Republic of Korea 0.00
Russian Federation 0.04
Senegal –0.04
Sierra Leone 0.02
Sri Lanka 0.02
Thailand –0.03
Turkey 0.10
Uganda 0.00
United Republic of Tanzania 0.04
United States of America –0.05
Uruguay 0.03
Venezuela (Bolivarian Republic of) –0.48
Vietnam 0.00

Unit: t CO₂‑eq /ha rice paddies/yr

Afghanistan 4.78
Argentina 7.93
Bangladesh 4.81
Benin 6.74
Bolivia (Plurinational State of) 7.85
Brazil 7.85
Burkina Faso 6.68
Cambodia 6.22
Cameroon 6.71
Chad 6.72
China 7.21
Colombia 7.21
Côte d'Ivoire 6.73
Democratic People's Republic of Korea 7.23
Democratic Republic of the Congo 6.71
Dominican Republic 7.69
Ecuador 7.77
Egypt 6.56
Ghana 6.76
Guinea 6.72
Guinea-Bissau 6.72
Guyana 7.79
India 4.73
Indonesia 6.31
Iran (Islamic Republic of) 9.52
Italy 9.57
Japan 7.27
Lao People's Democratic Republic 6.23
Liberia 6.72
Madagascar 6.71
Malaysia 6.20
Mali 6.20
Mozambique 6.72
Myanmar 6.25
Nepal 4.79
Nigeria 6.72
Pakistan 4.71
Paraguay 7.86
Peru 7.95
Philippines 6.21
Republic of Korea 7.20
Russian Federation 9.61
Senegal 6.67
Sierra Leone 6.73
Sri Lanka 4.77
Thailand 6.18
Turkey 9.67
Uganda 6.71
United Republic of Tanzania 6.75
United States of America 4.45
Uruguay 7.88
Venezuela (Bolivarian Republic of) 7.38
Vietnam 6.20

For conventional paddy rice, we assumed an initial cost of US$0 because many millions of hectares of paddies are already in place (Table 2). We used regional per-hectare average profits from Damania et al. (2024) as the source for net profit per year. Because the initial cost per hectare is US$0, the net cost per hectare is the negative of the per-hectare annual profit.

Table 2. Net cost and profit of conventional paddy rice by region in 2023.

Unit: US$/ha rice paddies

Africa 0.00
East Asia 0.00
Europe 0.00
North America 0.00
South America 0.00
South Asia 0.00
Southeast Asia 0.00

Unit: US$/ha rice paddies/yr

Africa 457.34
East Asia 543.67
Europe 585.43
North America 356.27
South America 285.69
South Asia 488.85
Southeast Asia 322.13

Unit: US$/ha rice paddies/yr

Africa -457.34
East Asia -543.67
Europe -585.43
North America -356.27
South America -285.69
South Asia -488.85
Southeast Asia -322.13

For noncontinuous flooding, we assumed an initial cost of US$0 because no new inputs or changes to paddy infrastructure are required in most cases. Median impact on net profit was an increase of 17% based on nine data points from seven sources. National results are shown in Table 3.

We assumed nutrient management has an initial cost of US$0 because in many cases, nutrient management begins with reducing the overapplication of fertilizer. Here we used the mean value from Gu et al. (2023), a savings of US$507.8/t nitrogen. We used our national-level data on overapplication of nitrogen to calculate savings per hectare. National results are shown in Table 3.

Combined Net Profit per Hectare

Net profit per hectare varies by country due to regional and some country-specific variables. Country-by-country results are shown in Table 3.

Net Net Cost Compared to Conventional Paddy Rice

Net net cost varies by country. Country-by-country results are shown in Table 3.

Table 3. Net cost and profit of noncontinuous flooding with nutrient management by region.

Unit: US$/ha rice paddies

Afghanistan 0.00
Argentina 0.00
Bangladesh 0.00
Benin 0.00
Bolivia (Plurinational State of) 0.00
Brazil 0.00
Burkina Faso 0.00
Cambodia 0.00
Cameroon 0.00
Chad 0.00
China 0.00
Colombia 0.00
Cote d'Ivoire 0.00
Democratic People's Republic of Korea 0.00
Democratic Republic of the Congo 0.00
Dominican Republic 0.00
Ecuador 0.00
Egypt 0.00
Ghana 0.00
Guinea 0.00
Guinea–Bissau 0.00
Guyana 0.00
India 0.00
Indonesia 0.00
Iran (Islamic Republic of) 0.00
Italy 0.00
Japan 0.00
Lao People's Democratic Republic 0.00
Liberia 0.00
Madagascar 0.00
Malaysia 0.00
Mali 0.00
Mozambique 0.00
Myanmar 0.00
Nepal 0.00
Nigeria 0.00
Pakistan 0.00
Paraguay 0.00
Peru 0.00
Philippines 0.00
Republic of Korea 0.00
Russian Federation 0.00
Senegal 0.00
Sierra Leone 0.00
Sri Lanka 0.00
Thailand 0.00
Turkey 0.00
Uganda 0.00
United Republic of Tanzania 0.00
United States of America 0.00
Uruguay 0.00
Venezuela (Bolivarian Republic of) 0.00
Vietnam 0.00

Non-continuous flooding and nutrient management.

Unit: US$/ha rice paddies/yr

Afghanistan 573.4
Argentina 354.8
Bangladesh 576.7
Benin 535.1
Bolivia (Plurinational State of) 354.1
Brazil 363.4
Burkina Faso 553.3
Cambodia 377.8
Cameroon 543.7
Chad 535.1
China 675.1
Colombia 397.7
Cote d'Ivoire 535.8
Democratic People's Republic of Korea 654.6
Democratic Republic of the Congo 535.6
Dominican Republic 428.4
Ecuador 390.3
Egypt 802.2
Ghana 535.5
Guinea 538.5
Guinea–Bissau 539.2
Guyana 382.0
India 607.9
Indonesia 382.3
Iran (Islamic Republic of) 726.7
Italy 567.9
Japan 636.0
Lao People's Democratic Republic 377.0
Liberia 535.3
Madagascar 535.0
Malaysia 401.2
Mali 561.0
Mozambique 535.5
Myanmar 380.7
Nepal 575.2
Nigeria 537.1
Pakistan 610.0
Paraguay 385.9
Peru 351.7
Philippines 399.5
Republic of Korea 678.2
Russian Federation 475.2
Senegal 569.9
Sierra Leone 535.1
Sri Lanka 591.1
Thailand 407.7
Turkey 694.5
Uganda 543.3
United Republic of Tanzania 537.4
United States of America 490.4
Uruguay 377.6
Venezuela (Bolivarian Republic of) 546.2
Vietnam 416.6

Non-continuous flooding and nutrient management.

Unit: US$/ha rice paddies/yr

Afghanistan -573.4
Argentina -354.8
Bangladesh -576.7
Benin -535.1
Bolivia (Plurinational State of) -354.1
Brazil -363.4
Burkina Faso -553.3
Cambodia -377.8
Cameroon -543.7
Chad -535.1
China -675.1
Colombia -397.7
Cote d'Ivoire -535.8
Democratic People's Republic of Korea -654.6
Democratic Republic of the Congo -535.6
Dominican Republic -428.4
Ecuador -390.3
Egypt -802.2
Ghana -535.5
Guinea -538.5
Guinea–Bissau -539.2
Guyana -382.0
India -607.9
Indonesia -382.3
Iran (Islamic Republic of) -726.7
Italy -567.9
Japan -636.0
Lao People's Democratic Republic -377.0
Liberia -535.3
Madagascar -535.0
Malaysia -401.2
Mali -561.0
Mozambique -535.5
Myanmar -380.7
Nepal -575.2
Nigeria -537.1
Pakistan -610.0
Paraguay -385.9
Peru -351.7
Philippines -399.5
Republic of Korea -678.2
Russian Federation -475.2
Senegal -569.9
Sierra Leone -535.1
Sri Lanka -591.1
Thailand -407.7
Turkey -694.5
Uganda -543.3
United Republic of Tanzania -537.4
United States of America -490.4
Uruguay -377.6
Venezuela (Bolivarian Republic of) -546.2
Vietnam -416.6

Non-continuous flooding and nutrient management.

Unit: US$/ha rice paddies/yr

Afghanistan -1,062
Argentina -640.5
Bangladesh -1,065
Benin -992.4
Bolivia (Plurinational State of) -639.8
Brazil -649.0
Burkina Faso -1,010
Cambodia -699.9
Cameroon -1,001
Chad -992.5
China -1,219
Colombia -683.4
Cote d'Ivoire -993.2
Democratic People's Republic of Korea -1,198
Democratic Republic of the Congo -992.9
Dominican Republic -714.1
Ecuador -676.0
Egypt -1,387
Ghana -992.8
Guinea -995.8
Guinea–Bissau -996.5
Guyana -667.7
India -1,096
Indonesia -704.5
Iran (Islamic Republic of) -1,312
Italy -1,053
Japan -1,179
Lao People's Democratic Republic -699.1
Liberia -992.6
Madagascar -992.4
Malaysia -723.3
Mali -1,018
Mozambique -992.8
Myanmar -702.8
Nepal -1,064
Nigeria -994.5
Pakistan -1,098
Paraguay -671.6
Peru -637.4
Philippines -721.6
Republic of Korea -1,221
Russian Federation -865.9
Senegal -1,027
Sierra Leone -992.4
Sri Lanka -1,080
Thailand -729.8
Turkey -1,279
Uganda -1,000
United Republic of Tanzania -994.7
United States of America -846.7
Uruguay -663.3
Venezuela (Bolivarian Republic of) -831.9
Vietnam -738.8

Non-continuous flooding and nutrient management.

Unit: US$/t CO₂‑eq  

Afghanistan -222.1
Argentina -80.82
Bangladesh -221.5
Benin -147.2
Bolivia (Plurinational State of) -81.49
Brazil -82.60
Burkina Faso -151.2
Cambodia -112.5
Cameroon -149.3
Chad -147.7
China -168.9
Colombia -87.77
Cote d'Ivoire -147.6
Democratic People's Republic of Korea -165.8
Democratic Republic of the Congo -147.9
Dominican Republic -92.82
Ecuador -86.99
Egypt -211.5
Ghana -146.9
Guinea -148.1
Guinea–Bissau -148.2
Guyana -85.72
India -232.1
Indonesia -111.5
Iran (Islamic Republic of) -137.8
Italy -110.0
Japan -162.2
Lao People's Democratic Republic -112.2
Liberia -147.6
Madagascar -147.9
Malaysia -116.6
Mali -152.2
Mozambique -147.7
Myanmar -112.4
Nepal -222.2
Nigeria -148.0
Pakistan -233.3
Paraguay -85.41
Peru -80.22
Philippines -116.1
Republic of Korea -169.7
Russian Federation -90.08
Senegal -154.0
Sierra Leone -147.5
Sri Lanka -226.3
Thailand -118.1
Turkey -132.3
Uganda -149.1
United Republic of Tanzania -147.3
United States of America -190.1
Uruguay -84.18
Venezuela (Bolivarian Republic of) -112.7
Vietnam -119.1

Non-continuous flooding and nutrient management.

Cost per unit climate impact

The cost per t CO₂‑eq varies by country. Country-by-country results are shown in Table 3. The global weighted average is a savings of US$175.0/t CO₂‑eq (Table 4). Note that this is the same for both 100- and 20-yr results.

Table 4. Weighted average cost per unit climate impact.

Unit: US$/t CO₂‑eq

Weighted average -175.0

Learning curve data are not available for improved rice cultivation.

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as gradualemergency brake, or delayed.

The noncontinuous flooding component of Improve Rice Production is an EMERGENCY BRAKE climate solution. It has a disproportionately fast impact after implementation because it reduces the short-lived climate pollutant methane. 

The nutrient management component is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

Adoption

Noncontinuous Flooding

Rigorous, up-to-date country-level data about the extent of noncontinuous flooding in rice production are in short supply. We found five sources reporting adoption in seven major rice-producing countries. We used these to create regional averages and applied them to all countries that produce more than 100,000 ha of rice (paddy and upland). The total estimated current adoption is 48.65 Mha, or 47% of global rice paddy area (Table 5). This should be considered an extremely rough estimate. 

The available sources encompass different forms of noncontinuous flooding, including alternate wetting and drying (Philippines, Vietnam, Bangladesh), mid-season drainage (Japan), or both (China). 

Table 5. Current adoption level (2025).

Unit: Mha

mean 48.65

Noncontinuous flooding, ha installed.

Nutrient Management

We based nutrient management adoption on our analysis of the overapplication of nitrogen fertilizer on a national basis. Rather than calculate adoption in a parallel way to noncontinuous flooding, this approach provided a national average overapplication rate (the amount of nitrogen fertilizer which is applied that is not needed for crop growth and ends up as nitrous oxide emissions). We assume that every hectare of noncontinuous flooding is also using nutrient management. 

We assume the adoption of both noncontinuous flooding and nutrient management for each hectare.

Adoption trend information here takes the form of annual growth rate (%), with a median of 3.76% (Table 6). Adoption rate data are somewhat scarce. 

Table 6. Adoption trend.

Unit: %

25th percentile 3.00
median (50th percentile) 3.76
75th percentile 4.25

Percent annual growth rate.

There are barriers to adoption of these techniques and practices. Not all paddy rice is suitable for improved water management, and under certain conditions, undesirable yield reductions are possible (Bo et al., 2022). Other challenges include water access, coordinating water usage between multiple users, and ownership of water pumps (Nabuurs et al., 2022).

There are many challenges in estimating paddy rice land. Food and Agriculture Organization (FAO) statistics can overcount because land that produces more than one crop is double or triple counted. Satellite imagery is often blocked by clouds in the tropical humid areas where rice paddies are concentrated. 

A comprehensive effort to calculate total world rice paddy land reported 66.00 Mha of irrigated paddy and 63.00 Mha of rain-fed paddy (Salmon et al., 2015). Our own calculation of the combined paddy rice area of countries producing over 100,000 ha of rice found 104.1 Mha of paddy rice.

We summed high-resolution maps of paddy rice area appropriate for noncontinuous flooding (Bo et al., 2022) over maps of irrigated and rain-fed rice areas (Salmon et al., 2015) to determine a maximum adoption ceiling for each country. Several countries have already exceeded this threshold, and we included their higher adoption in our calculation. The sum of these, and therefore, the median adoption ceiling, is 77.53 Mha (Table 7).

Table 7. Adoption ceiling: upper limit for adoption level.

Unit: Mha

median 77.53

Mha of improved rice production installed.

Table 8. Range of achievable adoption levels.

Unit: Mha

Current Adoption 48.65
Achievable – Low 49.56
Achievable – High 77.53
Adoption Ceiling 77.53

Mha of improved rice production installed.

Given that both China and Japan have already attained adoption rates above our adoption ceiling (Bo et al., 2022; Zhang et al., 2019), we selected for our adoption ceiling our Achievable – High adoption level, which is 77.53 Mha (Table 8).

In contrast, the countries with the lowest adoption rates had rates under 3%. In the absence of a modest adoption example, we chose to use current adoption plus 10% as our Achievable – Low adoption level. This provides an adoption of 49.56 Mha.

As described under Adoption Ceiling above, adoption of nutrient management is already weighted based on regional or national adoption and should not be overcounted in the achievable range calculations.

Impacts

We calculated the potential impact of improved rice, on a 100-yr basis, at 0.10 Gt CO₂‑eq/yr from current adoption, and 0.10, 0.16, and 0.16 from Achievable – Low, Achievable – High, and Adoption Ceiling, respectively (Table 9). On a 20-yr basis, the totals are 0.29, 0.29, 0.46, and 0.46, respectively.

Table 9. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr

Current Adoption 0.10
Achievable – Low 0.10
Achievable – High 0.16
Adoption Ceiling 0.16

Unit: Gt CO₂‑eq/yr

Current Adoption 0.29
Achievable – Low 0.29
Achievable – High 0.46
Adoption Ceiling 0.46

The IPCC estimated a technical potential at 0.3 Gt CO₂‑eq/yr, with 0.2 Gt CO₂‑eq/yr as economically achievable at US$100/t CO₂ (100-yr basis; Nabuurs et al., 2022). Achieving the adoption ceiling of 76% of global flooded rice production could reduce rice paddy methane by 47% (Bo et al., 2022). Applying this percentage to the IPCC reported total paddy methane emissions of 0.49–0.73 Gt CO₂‑eq/yr yields a reduction of 0.23–0.34 Gt CO₂‑eq/yr (Nabuurs et al., 2022). Roe et al. (2021) calculated 0.19 Gt CO₂‑eq/yr. Note that these benchmarks only calculate methane from paddy rice, while we also addressed nitrous oxide from nutrient management.

The additional benefits of improved rice production arise from both practices (noncontinuous flooding and improved nutrient management) that form this solution. 

Health

Noncontinuous flooding can reduce the accumulation of arsenic in rice grains (Ishfaq et al., 2020). Arsenic is a carcinogen that is responsible for thousands of premature deaths in South and Southeast Asia (Jameel et al., 2021). The amount of arsenic reduced can vary by 0–90% depending upon the timing of the wetting and drying periods (Ishfaq et al., 2020).

Land Resources

Better nutrient management improves soil fertility and health, increasing resilience to extreme heat and droughts. Noncontinuous flooding also slows down the rate of soil salinization, protecting soil from degradation (Carrijo et al., 2017). 

Water Resources

Rice irrigation is responsible for 40% of all freshwater use in Asia, and rice requires two to three times more water per metric ton of grain than other cereals (Surendran et al., 2021). Field studies across South and Southeast Asia have shown that noncontinuous flooding can typically reduce irrigation requirements 20–30% compared to conventional flooded systems (Suwanmaneepong et al., 2023; Carrijo et al., 2017) without adversely affecting rice yield or grain quality. This reduction in water usage alleviates pressure on water resources in drought-prone areas (Alauddin et al., 2020).

Adoption of noncontinuous flooding up to the adoption ceiling of 76% would reduce rice irrigation needs by 25%. 

Water Quality

Both noncontinuous flooding and improved nutrient management reduce water pollution. Nitrogen utilization is generally poor using existing growing techniques, with two-thirds of the nitrogen fertilizer being lost through surface runoff and denitrification (Zhang et al., 2021). While noncontinuous flooding is primarily a water-efficiency and methane reduction technique, it can improve nitrogen use efficiency and reduce nitrogen runoff into water bodies (Liang et al., 2017; Liang et al., 2023). Improved nutrient management also reduces the excess fertilizers that could end up in local water bodies. Both mechanisms can mitigate eutrophication and harmful algal blooms, protect aquatic ecosystems, and ensure safer drinking water supplies (Bijay-Sing and Craswell, 2021). 

Other

Caveats like additionality and permanence do not apply to improve rice production as described here. If its carbon sequestration component were included, those caveats would apply.

Not all paddies are suitable, with variables including soil type, irrigation infrastructure and ownership, community partitioning and scheduling of water resources, field size, and more (Nabuurs et al., 2022; Enriquez et al., 2021).

Many rice farmers in Asia do not directly control irrigation access, but instead use a municipal system, which is not always available when needed for noncontinuous flooding production. In addition, they may not actually experience cost savings, as pricing may be based on area rather than amount of water. An additional change is that multiple plots owned or rented by multiple farmers may be irrigated by a single irrigation gate, meaning that all must agree to an irrigation strategy. Generally speaking, pump-based irrigation areas see the best adoption, with poor adoption in gravity-based irrigation system areas. Improved irrigation infrastructure is necessary to increase adoption of noncontinuous flooding (Enriquez et al., 2021). 

Continuously flooded paddies have lower weed pressure than noncontinuous paddies, so noncontinuous flooding can raise labor costs or increase herbicide use. Not all rice varieties grow well in noncontinuous flooding (Li et al., 2024). In addition, it is difficult for farmers, especially smallholders, to monitor soil moisture level, which makes determining the timing of the next irrigation difficult (Livsey et al., 2019). 

In some cases, rice yields are reduced (Nabuurs et al., 2022). However, this has been excluded from our calculations because we worked from the adoption ceiling of Bo et al. (2022), which explicitly addresses the question of maximum adoption without reducing yields.

Long-term impacts on soil health of water-saving irrigation strategies have not been widely studied, but a meta-analysis by Livsey et al. (2019) indicates a risk of decreases in soil carbon and fertility.

We did not identify any aligned or competing interactions with other solutions.

There is high consensus on the effectiveness and potential of noncontinuous flooding and nutrient management (Jiang et al., 2019; Zhang et al., 2023; Nabuurs et al., 2022; Qian et al., 2023). 

Hergoualc’h et al. (2019) describe methane reduction and associated nitrous oxide increase from noncontinuous flooding in detail(2019). Bo et al. (2022) calculate that 76% of global rice paddy area is suitable to switch to noncontinuous flooding without reducing yields. Carlson et al. (2016) provide emissions intensities for croplands, including rice production. Ludemann et al. (2024) provide country-by-country and crop-by-crop fertilizer use data. Qian et al. (2023) review methane emissions production and reduction potential.

The results presented in this document summarize findings from 12 reviews and meta-analyses and 26 original studies reflecting current evidence from countries across the Asian rice production region. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

Take Action

Looking to get involved? Below are some key actions for this solution that can get you started, arranged according to different roles you may play in your professional or personal life.

These actions are meant to be starting points for involvement and are not intended to be prescriptive or necessarily suggest they are the most important or impactful actions to take. We encourage you to explore and get creative!

Lawmakers and Policymakers

  • Set national targets for improving rice production and incorporate them into planning documents such as Nationally Determined Contributions.
  • If possible and appropriate, encourage rice farmers to adopt noncontinuous flooding.
  • Use policies and regulations to improve nutrient management by focusing on the four principles – right rate, right type of fertilizer, right time, and right place.
  • Invest in research and development to improve rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Invest in research and development to improve water monitoring technology and discover alternative fertilizers.
  • Improve the reliability of water irrigation systems.
  • Work with farmers and private organizations to improve data collection on advanced cultivation uptake and water management.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Practitioners

  • Practice noncontinuous flooding.
  • Take advantage of financial incentives such as tax rebates and subsidies for improved rice cultivation.
  • Improve nutrient management by focusing on the four principles – right rate, right type of fertilizer, right time, and right place.
  • Plant improved rice varieties that require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Work with policymakers and private organizations to improve data collection on advanced cultivation uptake and water management.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Business Leaders

  • Source food from farms that practice improved rice cultivation.
  • Invest in companies that utilize improved rice cultivation techniques or produce the necessary inputs.
  • Promote products that employ improved rice cultivation techniques and educate consumers about the importance of the practice.
  • Enter into offtake agreements for rice grown with improved techniques.
  • Invest in research and development to improve rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Invest in research and development to improve water monitoring technology and identify alternative fertilizers.
  • Work with farmers and private organizations to improve data collection on advanced cultivation uptake and water management.
  • Advocate to policymakers for improved rice cultivation techniques, incentives, and regulations.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Nonprofit Leaders

  • Source food from farms that practice improved rice cultivation.
  • Start model farms to demonstrate techniques, conduct experiments, and educate local farmers.
  • Engage with businesses to encourage corporate responsibility and/or monitor rice production.
  • Help develop rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Help improve water monitoring technology and develop alternative fertilizers.
  • Work with farmers and other private organizations to improve data collection on advanced cultivation uptake and water management.
  • Advocate to policymakers for improved rice cultivation techniques, incentives, and regulations.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Investors

  • Ensure portfolio companies and company procurement use improved rice cultivation techniques.
  • Offer financial services, including low-interest loans, micro-financing, and grants to support improving rice cultivation.
  • Invest in electronically-traded funds (ETFs); environmental, social and governance (ESG) funds; and green bonds issued by companies committed to improved rice cultivation.
  • Invest in companies developing technologies that support improved nutrient management, such as precision fertilizer applicators, alternative fertilizers, soil management equipment, and software.
  • Invest in start-ups that aim to improve rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Philanthropists and International Aid Agencies

  • Work with agricultural supply chain sources to ensure partners employ improved rice production methods, if relevant.
  • Start model farms to demonstrate techniques, conduct experiments, and educate local farmers.
  • Offer financial services, including low-interest loans, micro-financing, and grants to support improving rice cultivation.
  • Engage with businesses to encourage corporate responsibility and/or monitor rice production.
  • Help develop rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Help improve water monitoring technology and identify alternative fertilizers.
  • Work with farmers and other private organizations to improve data collection on advanced cultivation uptake and water management.
  • Advocate to policymakers for improved rice cultivation techniques, incentives, and regulations.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Thought Leaders

  • Source rice from farms that practice improved rice cultivation.
  • Start model farms to demonstrate techniques, conduct experiments, and educate local farmers.
  • Engage with businesses to encourage corporate responsibility and/or monitor rice production.
  • Help develop rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.
  • Help improve water monitoring technology and identify alternative fertilizers.
  • Work with farmers and other private organizations to improve data collection on advanced cultivation uptake and water management.
  • Advocate to policymakers for improved rice cultivation techniques, incentives, and regulations.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

Technologists and Researchers

  • Improve technology and cost-effectiveness of precision fertilizer application, slow-release fertilizer, alternative organic fertilizers, nutrient recycling, and monitoring equipment.
  • Create tracking and monitoring software to support farmers' decision-making.
  • Research the application of AI and robotics for precise fertilizer application and water management.
  • Improve data and analytics to monitor soil and water quality, assist farmers, support policymaking, and assess the impacts of policies.
  • Improve rice methane emissions modeling and monitoring using all available technologies such as satellites, low-flying instruments, and on-the-ground methods.
  • Develop education and training applications to promote improved rice cultivation techniques and provide real-time feedback.
  • Improve data collection on water management and advanced cultivation uptake.
  • Improve rice varieties to require less water, have shorter growth periods, produce higher yields, and tolerate more stress.

Communities, Households, and Individuals

  • Purchase rice from farms or suppliers that practice improved rice cultivation.
  • Engage with businesses to encourage corporate responsibility and/or monitor rice production.
  • Work with farmers and other private organizations to improve data collection on advanced cultivation uptake and water management.
  • Advocate to policymakers for improved rice cultivation techniques, incentives, and regulations.
  • Join, create, or participate in partnerships or certification programs dedicated to improving rice cultivation.

“Take Action” Sources

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Roe, S., Streck, C., Beach, R., Busch, J., Chapman, M., Daioglou, V., Deppermann, A., Doelman, J., Emmet-Booth, J., Engelmann, J., Fricko, O., Frischmann, C., Funk, J., Grassi, G., Griscom, B., Havlik, P., Hanssen, S., Humpenöder, F., Landholm, D., LOmax, G., Lehmann, J., Mesnildrey, L., Nabuurrs, G., Popp, A., Rivard, C., Sanderman, J., Sohngen, B., Smith, P., Stehfest, E., Woolf, D., & Lawrence, D. (2021). Land‐based measures to mitigate climate change: Potential and feasibility by country. Global Change Biology27(23), 6025–6058. Link to source: https://doi.org/10.1111/gcb.15873

Salmon, J. M., Friedl, M. A., Frolking, S., Wisser, D., & Douglas, E. M. (2015). Global rain-fed, irrigated, and paddy croplands: A new high resolution map derived from remote sensing, crop inventories and climate data. International Journal of Applied Earth Observation and Geoinformation38, 321–334. Link to source: https://doi.org/10.1016/j.jag.2015.01.014

Surendran, U., Raja, P., Jayakumar, M., & Subramoniam, S. R. (2021). Use of efficient water saving techniques for production of rice in India under climate change scenario: A critical review. Journal of Cleaner Production309Link to source: https://doi.org/10.1016/j.jclepro.2021.127272

Suwanmaneepong, S., Kultawanich, K., Khurnpoon, L., Sabaijai, P. E., Cavite, H. J., Llones, C., Lepcha, N., & Kerdsriserm, C. (2023). Alternate Wetting and Drying as Water-Saving Technology: An Adoption Intention in the Perspective of Good Agricultural Practices (GAP) Suburban Rice Farmers in Thailand. Water, 15(3), Article 402. Link to source: https://doi.org/10.3390/w15030402

Xia, L., Lam, S. K., Chen, D., Wang, J., Tang, Q., & Yan, X. (2017). Can knowledge‐based N management produce more staple grain with lower greenhouse gas emission and reactive nitrogen pollution? A meta‐analysis. Global change biology23(5), 1917–1925. Link to source: https://doi.org/10.1111/gcb.13455

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Appendix

In this analysis, we calculated the potential for reducing crop nitrogen inputs and associated nitrous oxide emissions by integrating spatially explicit, crop-specific data on nitrogen inputs, crop yields, attainable yields, irrigated extent, and climate. Broadly, we calculated a “target” yield-scaled nitrogen input rate based on pixels with low yield gaps and calculated the difference between nitrous oxide emissions under the current rate and under the hypothetical target emissions rate, using nitrous oxide emissions factors disaggregated by fertilizer type and climate. 

Emissions Factors

We used Tier 1 emissions factors from the IPCC 2019 Refinement to the 2006 Guidelines for National Greenhouse Gas Inventories, including direct emissions factors as well as indirect emissions from volatilization and leaching pathways. Direct emissions factors represent the proportion of applied nitrogen emitted as nitrous oxide, while we calculated volatilization and leaching emissions factors by multiplying the proportion of applied nitrogen lost through these pathways by the proportion of volatilized or leached nitrogen ultimately emitted as nitrous oxide. Including both direct and indirect emissions, organic and synthetic fertilizers emit 4.97 kg CO₂‑eq/kg nitrogen and 8.66 kg CO₂‑eq/kg nitrogen, respectively, in wet climates, and 2.59 kg CO₂‑eq/kg nitrogen and 2.38 kg CO₂‑eq/kg nitrogen in dry climates. We included uncertainty bounds (2.5th and 97.5th percentiles) for all emissions factors. 

We classified each pixel as “wet” or “dry” using an aridity index (AI) threshold of 0.65, calculated as the ratio of annual precipitation to potential evapotranspiration (PET) from TerraClimate data (1991–2020), based on a threshold of 0.65. For pixels in dry climates that contained irrigation, we took the weighted average of wet and dry emissions factors based on the fraction of cropland that was irrigated (Mehta et al., 2024). We excluded irrigated rice from this analysis due to large differences in nitrous oxide dynamics in flooded rice systems.

Current, Target, and Avoidable Nitrogen Inputs and Emissions

Using highly disaggregated data on nitrogen inputs from Adalibieke et al. (2024) for 21 crop groups, we calculated total crop-specific inputs of synthetic and organic nitrogen. We then averaged over 2016–2020 to reduce the influence of interannual variability in factors like fertilizer prices. These values are subsequently referred to as “current” nitrogen inputs. We calculated nitrous oxide emissions under current nitrogen inputs as the sum of the products of nitrogen inputs and the climatically relevant emissions factors for each fertilizer type.

Next, we calculated target nitrogen application rates in terms of kg nitrogen per ton of crop yield using data on actual and attainable yields for 17 crops from Gerber et al., 2024. For each crop, we first identified pixels in which the ratio of actual to attainable yields was above the 80th percentile globally. The target nitrogen application rate was then calculated as the 20th percentile of nitrogen application rates across low-yield-gap pixels. Finally, we calculated total target nitrogen inputs as the product of actual yields and target nitrogen input rates. We calculated hypothetical nitrous oxide emissions from target nitrogen inputs as the product of nitrogen inputs and the climatically relevant emissions factor for each fertilizer type.

The difference between current and target nitrogen inputs represents the amount by which nitrogen inputs could hypothetically be reduced without compromising crop productivity (i.e., “avoidable” nitrogen inputs). We calculated avoidable nitrous oxide emissions as the difference between nitrous oxide emissions with current nitrogen inputs and those with target nitrogen inputs. For crops for which no yield or attainable yield data were available, we applied the average percent reduction in nitrogen inputs under the target scenario from available crops to the nitrogen input data for missing crops to calculate the avoidable nitrogen inputs and emissions. 

This simple and empirically driven method aimed to identify realistically low but nutritionally adequate nitrogen application rates by including only pixels with low yield gaps, which are unlikely to be substantially nutrient-constrained. We did not control for other factors affecting nitrogen availability, such as historical nutrient application rates or depletion, rotation with nitrogen fixing crops, or tillage and residue retention practices.

Credits

Lead Fellow

  • Eric Toensmeier

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Yusuf Jameel, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • James Gerber, Ph.D.

  • Hannah Henkin

  • Zoltan Nagy, Ph.D.

  • Ted Otte

  • Paul C. West, Ph.D.

  • Greenhouse gas quantity expressed relative to CO₂ with the same warming impact over 100 years, calculated by multiplying emissions by the 100-yr GWP for the emitted gases.

  • Greenhouse gas quantity expressed relative to CO with the same warming impact over 20 years, calculated by multiplying emissions by the 20-yr GWP for the emitted gases.

  • 8th World Congress on Conservation Agriculture

  • Reducing greenhouse gas concentrations in the atmosphere by preventing or reducing emissions.

  • The process of increasing acidity.

  • The extent to which emissions reduction or carbon removal is above and beyond what would have occurred without implementing a particular action or solution.

  • An upper limit on solution adoption based on physical or technical constraints, not including economic or policy barriers. This level is unlikely to be reached and will not be exceeded.

  • The quantity and metric to measure implementation for a particular solution that is used as the reference unit for calculations within that solution.

  • A composting method in which organic waste is processed in freestanding piles that can be aerated actively with forced air or passively by internal convection.

  • The interactions of aerodynamic forces and flexible structures, often including the stucture's control system.

  • A process in which microbes break down organic materials in the presence of oxygen. This process converts food and green waste into nutrient-rich compost.

  • Farming practices that work to create socially and ecologically sustainable food production.

  • Addition of trees and shrubs to crop or animal farming systems.

  • Spread out the cost of an asset over its useful lifetime.

  • A crop that live one year or less from planting to harvest; also called annual.

  • aerated static piles

  • black carbon

  • Made from material of biological origin, such as plants, animals, or other organisms.

  • A renewable energy source generated from organic matter from plants and/or algae.

  • An energy source composed primarily of methane and CO that is produced by microorganisms when organic matter decomposes in the absence of oxygen.

  • Carbon stored in biological matter, including soil, plants, fungi, and plant products (e.g., wood, paper, biofuels). This carbon is sequestered from the atmosphere but can be released through decomposition or burning.

  • Living or dead renewable matter from plants or animals, not including organic material transformed into fossil fuels. Peat, in early decay stages, is partially renewable biomass.

  • Biogas refined to the same quality as natural gas. CO₂ and impurities are removed, and the biomethane can be distributed and used in existing natural gas technologies.
     

  • A type of carbon sequestration that captures carbon from CO via photosynthesis and stores it in soils, sediments, and biomass, distinct from sequestration through chemical or industrial pathways.

  • A climate pollutant, also called soot, produced from incomplete combustion of organic matter, either naturally (wildfires) or from human activities (biomass or fossil fuel burning).

  • A secure, decentralized way of digitally tracking transactions that could be used to improve the transparency and efficiency of carbon markets. 

  • High-latitude (>50°N or >50°S) climate regions characterized by short growing seasons and cold temperatures.

  • The components of a building that physically separate the indoors from the outdoor environment.

  • Businesses involved in the sale and/or distribution of solution-related equipment and technology, and businesses that want to support adoption of the solution.

  • A chemical reaction involving heating a solid to a high temperature; to make cement clinker, limestone is calcined into lime in a process that requires high heat and produces CO.

  • The ratio of the actual electricity an energy technology generates over a period of time to the maximum it could have produced if it operated at full capacity continuously.

  • A four-wheeled passenger vehicle.

  • Average number of people traveling in a car per trip.

  • Technologies that collect CO before it enters the atmosphere, preventing emissions at their source. Collected CO can be used onsite or in new products, or stored long term to prevent release.

  • A greenhouse gas that is naturally found in the atmosphere. Its atmospheric concentration has been increasing due to human activities, leading to warming and climate impacts.

  • Total GHG emissions resulting from a particular action, material, technology, or sector.

  • Amount of GHG emissions released per activity or unit of production. 

  • A marketplace where carbon credits are purchased and sold. One carbon credit represents activities that avoid, reduce, or remove one metric ton of GHG emissions.

  • A colorless, odorless gas released during the incomplete combustion of fuels containing carbon. Carbon monoxide can harm health and be fatal at high concentrations.

  • The time it takes for the emissions reduction from a measure to equal the emissions invested in implementing the measure.

  • Activities or technologies that pull CO out of the atmosphere, including enhancing natural carbon sinks and deploying engineered sinks.

  • Long-term storage of carbon in soils, sediment, biomass, oceans, and geologic formations after removal of CO from the atmosphere or CO capture from industrial and power generation processes.

  • carbon capture and storage

  • carbon capture, utilization, and storage

  • A binding ingredient in concrete responsible for most of concrete’s life-cycle emissions. Cement is made primarily of clinker mixed with other mineral components.

  • chlorofluorocarbon

  • methane

  • Energy sources that have little to no negative environmental or climate impacts during operation relative to fossil fuel–based energy sources.

  • Gases or particles that have a planet-warming effect when released to the atmosphere. Some climate pollutants also cause other forms of environmental damage.

  • A binding ingredient in cement responsible for most of the life-cycle emissions from cement and concrete production.

  • A waste management process where waste is made into the same original product, preserving quality and value so materials can be reused multiple times while keeping resources in continuous use.

  • carbon monoxide

  • Neighbors, volunteer organizations, hobbyists and interest groups, online communities, early adopters, individuals sharing a home, and private citizens seeking to support the solution.

  • A solution that potentially lowers the benefit of another solution through reduced effectiveness, higher costs, reduced or delayed adoption, or diminished global climate impact.

  • A farming system that combines reduced tillage, cover crops, and crop rotations.

  • A risk-sharing financial agreement in which two parties (e.g., renewable generator, government) guarantee a fixed price (e.g., electricity price). If market prices fluctuate, one party pays the other the difference.

  • carbon dioxide

  • A  measure standardizing the warming effects of greenhouse gases relative to CO. CO-eq is calculated as quantity (metric tons) of a particular gas multiplied by its GWP.

  • carbon dioxide equivalent

  • Plant materials left over after a harvest, such as stalks, leaves, and seed husks.

  • A granular material made by crushing broken or waste glass.

  • direct air capture

  • Financial agreements in which government creditors forgive a portion of debt in exchange for specific conservation commitments.

  • The process of cutting greenhouse gas emissions (primarily CO) from a particular sector or activity.

  • An industrial process that removes printing ink from used or waste paper fibers, creating clean pulp that can be turned into new paper products.

  • A solution that works slower than gradual solutions and is expected to take longer to reach its full potential.

  • Microbial conversion of nitrate into inert nitrogen gas under low-oxygen conditions, which produces the greenhouse gas nitrous oxide as an intermediate compound.

  • Greenhouse gas emissions produced as a direct result of the use of a technology or practice.

  • A window consisting of two glass panes separated by a sealed gap and typically filled with air or an inert gas to improve the heat flow resistance.

  • A waste management system that transforms waste into different products of lower quality and value, making materials harder to recycle again and limiting reuse.

  • Ability of a solution to reduce emissions or remove carbon, expressed in CO-eq per installed adoption unit. Effectiveness is quantified per year when the adoption unit is cumulative over time.

  • A process that uses electric current to drive a reaction, such as using electricity to split water molecules into hydrogen and oxygen.

  • Greenhouse gas emissions accrued over the lifetime of a material or product, including as it is produced, transported, used, and disposed of.

  • Solutions that work faster than gradual solutions, front-loading their impact in the near term.

  • Methane produced by microbes in the digestive tracts of ruminant livestock, such as cattle, sheep and goats.

  • U.S. Environmental Protection Agency

  • expanded polystyrene

  • environmental, social, and governance

  • exchange-traded fund

  • A process triggered by an overabundance of nutrients in water, particularly nitrogen and phosphorus, that stimulates excessive plant and algae growth and can harm aquatic organisms.

  • Electric vehicle

  • An ecological process that releases water into the atmosphere as a gas from soil and ice (evaporation) and plants (transpiration).

     

  • The scientific literature that supports our assessment of a solution's effectiveness.

  • A group of human-made molecules that contain fluorine atoms. They are potent greenhouse gases with GWPs that can be hundreds to thousands times higher than CO.

  • Food, agriculture, land, and ocean

  • Food and Agriculture Organization of the United Nations

  • feed conversion ratio

  • The efficiency with which an animal converts feed into increased body mass, measured as the ratio of the weight of the feed given to weight gain. Lower FCR means less feed for the same growth.

  • Raw material inputs for manufacturing, processing, and managing waste.

  • Containing or consisting of iron.

  • A measure of fishing activity over time and area, commonly measured by number of trips, vessel time, or gear deployed.

  • food loss and waste

  • Food discarded during pre-consumer supply chain stages, including production, harvest, and processing.

  • Food discarded during pre-consumer supply chain stages, including production, harvest, and processing, along with food discarded wt the retail and consumer stages of the supply chain.

  • Food discarded at the retail and consumer stages of the supply chain.

  • Combustible materials found in Earth's crust that can be burned for energy, including oil, natural gas, and coal. They are formed from decayed organisms through prehistoric geological processes.

  • Unintentional leaks of gases or vapor into the atmosphere.

  • Unintentional leaks of gases or vapor into the atmosphere.

  • A group of countries representing the majority of the world's population, trade, and GDP. There are 19 member countries plus the European Union and the African Union

  • greenhouse gas

  • gigajoule or billion joules

  • The glass layers or panes in a window.

  • A measure of how effectively a gas traps heat in the atmosphere relative to CO. GWP converts greenhouse gases into CO-eq emissions based on their 20- or 100-year impacts.

  • A solution that has a steady impact on the atmosphere. Effectiveness is expected to be constant over time rather than having a higher impact in the near or long term.

  • A fixed income debt instrument focused on sustainable projects. Green bonds work in the same manner as traditional bonds and may be issued by corporations, financial institutions, and governments.

  • Biomass discarded during landscaping and gardening.

  • A gas that traps heat in the atmosphere, contributing to climate change.

  • The makeup of electricity generation on a power grid, showing the share contributed by various energy sources (e.g., coal, natural gas, nuclear, wind, solar, hydro) relative to total electricity production.

  • metric gigatons or billion metric tons

  • global warming potential

  • hectare

  • household air pollution

  • hydrochlorofluorocarbon

  • Number of years a person is expected to live without disability or other limitations that restrict basic functioning and activity.

  • A unit of land area comprising 10,000 square meters, roughly equal to 2.5 acres.

  • Hybrid electric car

  • hydrofluorocarbon

  • hydrofluoroolefin

  • hydrofluoroolefin

  • Particles and gases released from use of polluting fuels and technologies such as biomass cookstoves that cause poor air quality in and around the home.

  • heating, ventilation, air conditioning, and refrigeration

  • Organic compounds that contain hydrogen and carbon.

  • Human-made F-gases that contain hydrogen, fluorine, and carbon. They typically have short atmospheric lifetimes and GWPs hundreds or thousands times higher than CO

  • Human-made F-gases that contain hydrogen, fluorine, and carbon, with at least one double bond. They have low GWPs and can be climate-friendly alternatives to HFC refrigerants.

  • Hydrogen is a gas that can be a fuel, feedstock, or means of storing energy. It generates water instead of GHG when burned, but the process of producing it can emit high levels of GHGs. 

  • Hydrogen is a gas that can be a fuel, feedstock, or means of storing energy. It generates water instead of GHG when burned, but the process of producing it can emit high levels of GHGs. 

  • A recycling process that separates fibers from contaminants for reuse. Paper or cardboard is mixed with water to break down fibrous materials into pulp.

  • internal combustion engine

  • Aerobic decomposition of organic waste in a sealed container or bin/bay system. 

  • Greenhouse gas emissions produced as a result of a technology or practice but not directly from its use.

  • Device used to power vehicles by the intake, compression, combustion, and exhaust of fuel that drives moving parts.

  • The annual discount rate that balances net cash flows for a project over time. Also called IRR, internal rate of return is used to estimate profitability of potential investments.

  • Individuals or institutions willing to lend money in search of a return on their investment.

  • Intergovernmental Panel on Climate Change

  • Indigenous peoples’ land

  • Integrated pest management.

  • internal rate of return

  • International Union for Conservation of Nature

  • The most comprehensive global list of species threatened with extinction, maintained by the International Union for Conservation of Nature.

  • International agreement adopted in 2016 to phase down the use of high-GWP HFC F-gases over the time frame 2019–2047.

  • A measure of energy equivalent to the energy delivered by 1,000 watts of power over one hour.

  • kiloton or one thousand metric tons

  • kilowatt-hour

  • A land-holding system, e.g. ownership, leasing, or renting. Secure land tenure means farmers or other land users will maintain access to and use of the land in future years.

  • Gases, mainly methane and CO, created by the decomposition of organic matter in the absence of oxygen.

  • levelized cost of electricity

  • leak detection and repair

  • Regular monitoring for fugitive methane leaks throughout oil and gas, coal, and landfill sector infrastructure and the modification or replacement of leaking equipment.

  • Relocation of emissions-causing activities outside of a mitigation project area rather than a true reduction in emissions.

  • The rate at which solution costs decrease as adoption increases, based on production efficiencies, technological improvements, or other factors.

  • Percent decrease in costs per doubling of adoption.

  • A metric describing the expected break-even cost of generating electricity per megawatt-hour ($/MWh), combining costs related to capital, operation, and fuel (if used) and dividing by total output over the generator's lifetime.

  • landfill gas

  • Greenhouse gas emissions from the sourcing, production, use, and disposal of a technology or practice.

  • The total weight of an organism before any meat processing.

  • low- and middle-income countries

  • liquefied petroleum gas

  • land use change

  • A measure of the amount of light produced by a light source per energy input.

  • live weight

  • marginal abatement cost curve

  • Livestock grazing practices that strategically manage livestock density, grazing intensity, and timing. Also called improved grazing, these practices have environmental, soil health, and climate benefits, including enhanced soil carbon sequestration.

  • A tool to measure and compare the financial cost and abatement benefit of individual actions based on the initial and operating costs, revenue, and emission reduction potential.

  • Defined by the International Union for Conservation of Nature as: "A clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values." References to PAs here also include other effective area-based conservation measures defined by the IUCN. 

  • A facility that receives recyclable waste from residential, commercial, and industrial sources; separates, processes, and prepares them; and then sells them to manufacturers for reuse in new products.

  • A measure of energy equivalent to the energy delivered by one million watts of power over one hour.

  • A greenhouse gas with a short lifetime and high GWP that can be produced through a variety of mechanisms including the breakdown of organic matter.

  • A measure of mass equivalent to 1,000 kilograms (~2,200 lbs).

  • million hectares

  • Soils mostly composed of inorganic materials formed through the breakdown of rocks. Most soils are mineral soils, and they generally have less than 20% organic matter by weight.

  • A localized electricity system that independently generates and distributes power. Typically serving limited geographic areas, mini-grids can operate in isolation or interconnected with the main grid.

  • Reducing the concentration of greenhouse gases in the atmosphere by cutting emissions or removing CO.

  • megajoule or one million joules

  • Percent of trips made by different passenger and freight transportation modes.

  • Marine Protected Area

  • materials recovery facility

  • Municipal solid waste

  • megaton or million metric tons

  • Materials discarded from residential and commercial sectors, including organic waste, glass, metals, plastics, paper, and cardboard.

  • Megawatt-hour

  • micro wind turbine

  • square meter kelvins per watt (a measure of thermal resistance, also called R-value)

  • The enclosed housing at the top of a wind turbine tower that contains the main mechanical and electrical components of the turbine.

  • A commitment from a country to reduce national emissions and/or sequester carbon in alignment with global climate goals under the Paris Agreement, including plans for adapting to climate impacts.

  • A gaseous form of hydrocarbons consisting mainly of methane.

  • Chemicals found in nature that are used for cooling and heating, such as CO, ammonia, and some hydrocarbons. They have low GWPs and are ozone friendly, making them climate-friendly refrigerants.

  • Microbial conversion of ammonia or ammonium to nitrite and then to nitrate under aerobic conditions.

  • A group of air pollutant molecules composed of nitrogen and oxygen, including NO and NO.

  • A greenhouse gas produced during fossil fuel combustion and agricultural and industrial processes. NO is hundreds of times more potent than CO at trapping atmospheric heat, and it depletes stratospheric ozone.

  • Metals or alloys that do not contain significant amounts of iron.

  • Social welfare organizations, civic leagues, social clubs, labor organizations, business associations, and other not-for-profit organizations.

  • A material or energy source that relies on resources that are finite or not naturally replenished at the rate of consumption, including fossil fuels like coal, oil, and natural gas.

  • nitrogen oxides

  • nitrous oxide

  • The process of increasing the acidity of seawater, primarily caused by absorption of CO from the atmosphere.

  • An agreement between a seller who will produce future goods and a purchaser who commits to buying them, often used as project financing for producers prior to manufacturing.

  • Waste made of plant or animal matter, including food waste and green waste.

  • organic waste

  • Protected Area

  • Productive use of wet or rewetted peatlands that does not disturb the peat layer, such as for hunting, gathering, and growing wetland-adapted crops for food, fiber, and energy.

  • A legally protected area that lacks effective enforcement or management, resulting in minimal to no conservation benefit.

  • Airborne particles composed of solids and liquids.

  • A measure of transporting one passenger over a distance of one kilometer.

  • Incentive payments to landowners or managers to conserve natural resources and promote healthy ecological functions or ecosystem services.

  • Small, hardened pieces of plastic made from cooled resin that can be melted to make new plastic products.

  • The longevity of any greenhouse gas emission reductions or removals. Solution impacts are considered permanent if the risk of reversing the positive climate impacts is low within 100 years.

  • Payments for ecosystem services

  • A mixture of hydrocarbons, small amounts of other organic compounds, and trace amounts of metals used to produce products such as fuels or plastics.

  • Per- and polyfluoroalkyl substances, a class of synthetic chemicals that do not degrade easily in the environment. They can pollute the environment and can have negative impacts on human health.

  • Reduce the use of a material or practice over time.

  • Eliminate the use of a material or practice over time.

  • Plug-in hybrid electric car

  • Private, national, or multilateral organizations dedicated to providing aid through in-kind or financial donations.

  • An atmospheric reaction among sunlight, VOCs, and nitrogen oxide that leads to ground-level ozone formation. Ground-level ozone, a component of smog, harms human health and the environment.

  • The process by which sunlight is converted into electricity. When light hits certain materials, such as those in solar panels, it mobilizes electrons, creating an electric current.

  • polyisocyanurate

  • The adjustment of turbine blade angles around their long axis in which a control system rotates blades slightly forward or backward to regulate wind capture and optimize electricity generation.

  • passenger kilometer

  • particulate matter

  • Particulate matter 2.5 micrometers or less in diameter that can harm human health when inhaled.

  • Elected officials and their staff, bureaucrats, civil servants, regulators, attorneys, and government affairs professionals.

  • System in a vehicle that generates power and delivers it to the wheels. It typically includes an engine and/or motor, transmission, driveshaft, and differential.

  • Purchase Power Agreement.

  • People who most directly interface with a solution and/or determine whether the solution is used and/or available. 

  • A substance that is the starting material for a chemical reaction that forms a different substance.

  • Extraction of naturally occurring resources from the Earth, including mining, logging, and oil and gas refining. These resources can be used in raw or minimally processed forms to produce materials.

  • The process of converting inorganic matter, including carbon dioxide, into organic matter (biomass), primarily by photosynthetic organisms such as plants and algae.

  • Defined by the International Union for the Conservation of Nature as "A clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values". References to PAs here also include other effective area-based conservation measures defined by the IUCN. 

  • A process that separates and breaks down wood and other raw materials into fibers that form pulp, the base ingredient for making paper products.

  • polyurethane

  • Long-term contract between a company (the buyer) and a renewable energy producer (the seller).

  • photovoltaic

  • research and development

  • A situation in which improvements in efficiency or savings lead to consumers increasing consumption, partially or fully offsetting or exceeding the emissions or cost benefits.

  • renewable energy certificate

  • Chemical or mixture used for cooling and heating in refrigeration, air conditioning, and heat pump equipment. Refrigerants absorb and release heat as they move between states under changing pressure.

  • The amount of refrigerant needed for a particular refrigeration, air conditioning, or heat pump system.

  • A group of approaches to farming and ranching that emphasizes enhancing the health of soil by restoring its carbon content and providing other benefits to the farm and surrounding ecosystem.

  • A solution that can increase the beneficial impact of another solution through increased effectiveness, lower costs, improved adoption, enhanced global climate impact, and/or other benefits to people and nature.

  • A material or energy source that relies on naturally occuring and replenishing resources such as plant matter, wind, or sunlight.

  • A market-based instrument that tracks ownership of renewable energy generation.

  • The moldable form of raw plastic material, created by melting down waste or virgin plastics and serving as the building block for creating new plastic goods.

  • A class of animals with complex stomachs that can digest grass. Most grazing livestock are ruminants including cows, sheep, and goats along with several other species.

  • sustainable aviation fuel

  • A wetland ecosystem regularly flooded by tides and containing salt-tolerant plants, such as grasses and herbs.

  • Very large or small numbers are formatted in scientific notation. A positive exponent multiplies the number by powers of ten; a negative exponent divides the number by powers of ten.

  • Seasonal coefficient of performance

  • Sustainable Development Goals

  • Average units of heat energy released for every unit of electrical energy consumed, used to measure heat pump efficiency.

  • A practice in which multiple utility companies own and operate high-voltage power lines, sharing both costs and benefits.

  • A window consisting of one glass pane without any additional insulating layers.

  • Small-scale family farmers and other food producers, often with limited resources, usually in the tropics. The average size of a smallholder farm is two hectares (about five acres).

  • soil organic carbon

  • Carbon stored in soils, including both organic (from decomposing plants and microbes) and inorganic (from carbonate-containing minerals).

  • Carbon stored in soils in organic forms (from decomposing plants and microbes). Soil organic carbon makes up roughly half of soil organic matter by weight.

  • Biologically derived matter in soils, including living, dead, and decayed plant and microbial tissues. Soil organic matter is roughly half carbon on a dry-weight basis.

  • soil organic matter

  • A substance that takes up another liquid or gas substance, either by absorbtion or adsorption.

  • sulfur oxides

  • sulfur dioxide

  • The rate at which a climate solution physically affects the atmosphere after being deployed. At Project Drawdown, we use three categories: emergency brake (fastest impact), gradual, or delayed (slowest impact).

  • Climate regions between latitudes 23.4° to 35° above and below the equator characterized by warm summers and mild winters.

  • A polluting gas produced primarily from burning fossil fuels and industrial processes that directly harms the environment and human health.

  • A group of gases containing sulfur and oxygen that predominantly come from burning fossil fuels. They contribute to air pollution, acid rain, and respiratory health issues.

  • Processes, people, and resources involved in producing and delivering a product from supplier to end customer, including material acquisition.

  • Sport utility vehicle

  • metric ton

  • metric tons

  • Technology developers, including founders, designers, inventors, R&D staff, and creators seeking to overcome technical or practical challenges.

  • Climate regions between 35° to 50° above and below the equator characterized by moderate mean annual temperatures and distinct seasons, with warm summers and cold winters.

  • A measure of energy equivalent to the energy delivered by one trillion watts of power over one hour.

  • trifluoroacetic acid

  • trifluoroacetic acid

  • A measure of how well a material prevents heat flow, often called R-value or RSI-value for insulation. A higher R-value means better thermal performance.

  • Individuals with an established audience for their work, including public figures, experts, journalists, and educators.

  • Charges for disposal of materials paid to facility operators. Fees can be charged per ton of waste disposed or based on economic indicators such as the Consumer Price Index.

  • A window consisting of three panes of glass separated by two insulating inert gas-filled layers, providing more heat flow resistance than single or double glazing.

  • Low-latitude (23.4°S to 23.4°N) climate regions near the Equator characterized by year-round high temperatures and distinct wet and dry seasons.

  • Terawatt, equal to 1,000 gigawatts

  • terawatt-hour

  • United Nations

  • United Nations Environment Programme

  • Self-propelled machine for transporting passengers or freight on roads.

  • A measure of one vehicle traveling a distance of one kilometer.

  • Aerobic decomposition of organic waste by earthworms and microorganisms.

  • vehicle kilometer

  • volatile organic compound

  • Gases made of organic, carbon-based molecules that are readily released into the air from other solid or liquid materials. Some VOCs are greenhouse gases or can harm human health.

  • watt (a measure of power or energy transfer.)

  • Landscape waste, storm debris, wood processing residues, and recovered post-consumer wood.

  • A measure of power equal to one joule per second.

  • Aerobic decomposition of organic waste in long, narrow rows called windrows. Windrows are generally twice as long as they are wide.

  • A subset of forest ecosystems that may have sparser canopy cover,  smaller-stature trees, and/or trees characterized by basal branching rather than a single main stem.

  • extruded polystyrene

  • The rotation of the nacelle (the enclosed housing at the top of a wind turbine tower that contains the main mechanical and electrical components of the turbine) so that the rotor blades are always facing directly into the wind.

  • year

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