Predicted changes in variation of annual rainfall, length of growing period, and temperature by 2050

This series of maps shows predicted changes in different climate phenomena by 2050 using scenarios developed by the IPCC (Intergovernmental Panel for Climate Change). The impacts of climate change on the rangelands of the globe and on the vulnerability of the people who inhabit them will be severe and diverse, and will require multiple, simultaneous responses. Map C shows the rangeland areas in which the average annual temperature flips from below 8°C in the 2000s to above 8°C by the 2050s. It is possible that between now and the middle of the century the growing period in the rangelands where average temperature flip to above 8°C could expand and become increasingly suitable for some kinds of rangeland vegetation. Map D shows the rangeland areas with an average maximum temperature (both annual and during the primary growing season) that flips from below 35°C to greater than 35°C by 2050. This will be a critical threshold for rangeland vegetation and heat tolerance in some species.

Key figures

1. According to climate change simulations rangelands can expect changes in the coefficient of variation of annual rainfall i.e. its variability between 2000 and 2050. 12% or approximately 9,000,000 km² of rangelands can expect to see greater than 35% change, 10% or approximately 8,000,000 km² can expect 30-35% change, 20% or approximately 16, 000,000 km² can expect 25-30%, 18% or 14,000,000 km² can expect 20-25% change, 9% or approximately 7,000,000 km² can expect 0-20% and 32% or approximately 25,000,000 km² can expect no change at all.

2. 12% of rangelands (approximately 10,000,000 km²) are predicted to have more than a 20% loss of length of growing period between 2000 and 2050. 88% of rangelands (66,000,000 km²) of rangelands are predicted to have less than a 20% loss of length of growing period between 2000 and 2050.

3. In around 4% of rangelands (approximately 3,000,000 km²) the average annual temperature will flip from below 8°C in the 2000s to above 8°C by the 2050s. The remaining 96% will not flip and/or will do so to a lower temperature.

4. In around 16% of rangelands (approximately 12,000,000 km²) the average maximum temperature is predicted to flip from below 35°C to greater than 35°C by 2050. This flip will be a critical threshold for rangeland vegetation and heat tolerance in some species. In the remaining 84% of rangelands the temperature will not flip and/or will do so to a lower temperature.

Coefficient of variation of annual rainfall by 2050 in rangelands

Statistics

No	Rainfall CV status	Area km²
1	0 %	24,774,702
2	0-20 %	6,981,734
3	20 - 25 %	13,761,107
4	25 - 30 %	15,505,479
5	30 - 35 %	7,984,837
6	> 35 %	9,408,701
	Total	78,416,559

Sources

Source 1: Terrestial ecoregions of the World. World Wide Fund for Nature (WWF). Downloaded in 2021: https://globil-panda.opendata.arcgis.com/datasets/terrestrial-ecoregion…. Original source: Olson, D. M., Dinerstein, E., Wikramanayake, E. D., Burgess, N. D., Powell, G. V. N., Underwood, E. C., D'Amico, J. A., Itoua, I., Strand, H. E., Morrison, J. C., Loucks, C. J., Allnutt, T. F., Ricketts, T. H., Kura, Y., Lamoreux, J. F., Wettengel, W. W., Hedao, P., Kassem, K. R. 2001. Terrestrial ecoregions of the world: a new map of life on Earth. Bioscience 51(11):933-938.

Source 2:Projections to 2050 using a high-emissions scenario (RCP8.5) developed by the Intergovernmental Panel on Climate Change and data from an ensemble of 17 climate models taken from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) of the World Climate Research Programme.

Reference paper: Herrero M., Addison J., Bedelian C., Carabine E., Havlík P., Henderson B., van de Steeg J. & Thornton P.K. – Climate change and pastoralism: impacts, consequences and adaptation. Rev. Sci. Tech. Off. Int. Epiz., 2016, 35 (2), 417–433.

20% loss of length of growing period (LGP) between 2000 and 2050 found in rangelands

20 percent loss of length of growing period (LGP) between 2000 and 2050 found in rangelands

Statistics

No	LGP status	Area km²
1	< 20 % loss	68,228,113
2	> 20 % loss	9,644,714
	Total	77,872,827

Sources

Average Annual Temperature variation below 8°C in the 2000s to above 8°C by the 2050s found in rangelands

Statistics

No	AAT status	Area km²
1	< 8ºC	74,791,530
2	> 8ºC	3,081,541
	Total	77,873,071

Sources

Average maximum temperature flipping from below 35ºC to greater than 35 ºC by 2050 found in rangelands

Statistics

No	AMT status	Area km²
1	< 35ºC	66,201,053
2	> 35ºC	12,298,038
	Total	78,499,090

sources

Australia

Adapting to climate change in Australia’s rangelands

Angus Emmott

In line with current forecasts, Australia is set to experience substantial warming and more frequent extreme climate events as a result of climate change. Temperatures are forecast to increase with more frequent and intense heatwaves, continuing high variability in annual rainfall, increased intensity of heavy rainfall, a probable increase in the frequency and severity of drought and increased periods of high fire-danger weather are all likely to be experienced.

Changes will be required in extensive rangeland grazing herd management, including stocking rate decisions informed by longer-term (e.g. sub-seasonal to seasonal to multi-year) climate forecasts, changing heat-sensitive operations to relatively cooler months, and relocating fences and tracks away from more erodible lands. A longer-term transformational change is already taking place, with moves to a different form of livestock production, combined with drought-proofing activities and diversifying sources of income within and beyond the pastoral enterprise: adaptation has always been an ongoing challenge for Australian livestock producers and a feature of production systems.

The Northern Australia Climate Program (NACP) operates across the rangelands in the northern half of Australia. It improves existing climate models and forecasting tools, develops new products to meet the needs of pastoralists and builds the capacity of pastoralists to manage the challenges posed by future droughts or failed wet seasons as well as climate variability. Extension staff are local people, who are based across northern Australia, and run workshops and liaise with pastoralists in their region. Many are local pastoralists themselves, which give them credibility as well an understanding of the local context. In addition, at the national level, the federal government is in investing millions in a Future Drought Fund, with hubs around various states. Further such responses will continue to be needed together with policy change, structural adjustment and development of new breeds and technologies.

For more information see:

Bastin G, Stokes C, Green D and Forrest K (2014) Australian rangelands and climate change – pastoral production and adaptation. Ninti One Limited and CSIRO, Alice Springs. http://www.nintione.com.au/resource/AustralianRangelandsAndClimateChange_PastoralProduction.pdf

For more on the methods for the thresholds mapped:

https://cgspace.cgiar.org/handle/10568/3826 and https://www.ifpri.org/publication/atlas-african-agriculture-research-development

For more information on climate change impacts on pastoralism see Climate change and pastoralism: impacts, consequences and adaptation. M. Herrero, J. Addison, C. Bedelian, E. Carabine, P. Havlik, B. Henderson, J. van de Steeg and P. Thornton. Rev. Sci. Tech. Off. Int. Epiz (2016) Vol. 35 (2).

Terminologies used

CV of annual rainfall is an index, expressed as a percentage, of climatic risk. It estimates the rainfall variability in an area where the higher the CV, the more variable the year-to-year rainfall of an area is. LGP (length of growing period) is the average number of growing days per year (where rainfall and moisture stored in the soil exceeds half of potential evapotranspiration) and can be interpreted as a proxy for the number of grazing days too.

The source of all these projections to 2015 are made using a high-emissions scenario (RCP8.5) developed by the Intergovernmental Panel on Climate Change and data form an ensemble of 17 climate models taken from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) of the World climate Research Program.