The avoided impacts of climate change on crop production

Tom OsborneThanks to:Simon Gosling, Gillian Fraser, Helen Greatrex, Tim Wheeler, Nigel Arnell

Emissions scenarios

CO2 concentration

Local change in climate

Future crop yields

Global warming

Regional crop production

A1B, and AVOID mitigation scenarios

Pattern-scaling based upon GCMsecham5, hadcm3, ipsl, cgcm31,ccsm30

GLAM crop model at 0.5 resolutionMaize, soybean, wheat

MAGICC

@ 2030,2040,2050,…

∑(YieldGLAM x Areaobserved)

Global-GLAM crop model• Original GLAM developed by Challinor et al (2004).

Process-based crop growth and development with daily timestep.

• Crops: soybean, maize, wheat.• Climate: 0.5 resolution using CRU based climate data.

Daily weather generator.• Extent: suitable grid cells and sowing date determined

by separate algorithm.• Varieties: 3 for maize and soybean, 1 for wheat• Rain-fed simulation only. No irrigation.

1961-90 baseline: soybean

Wheat

Business-as-usual impact of climate change by 2050 on wheat production

Percentage of 2050 “business-as-usual” impact avoided with scenario: A1B-2016-5-L

CO2 fertilisation alters effectiveness (relative and absolute) of AVOID scenarios

Maize

Soybean

Conclusions• Wheat

– Effect of mitigation varies regionally– CO2 fertilisation influences effectiveness of mitigation

– Interaction with climate change

• Maize– Relative effectiveness of scenarios unaffected by GCM or

adaptation (as represented here)

• Soybean– Mitigation effectiveness insensitive to CO2 and adaptation– Positive CC impacts (S Asia) reduced by mitigation

Thank you

1961-90 baseline: maize

Inter-annual variability

Spatial variability

1961-90 baseline: wheat