Study offers new predictions of future temperature and rainfall across Asia

“Accurate predictions of future climate change are essential for providing reliable information to plan climate mitigation and adaptation measures. However, projections of Earth System Models are still considered undesirable. By applying the emergent constraint technique, our work successfully reduced the uncertainties of future projections of precipitation, temperature, and snow loss in Asia compared to the original CMIP6 outputs.”

“It is important to accurately estimate future climate changes. Our work shows that future increases in rainfall and temperature over Asia are likely to be smaller than previously thought.”

“Our work reveals that previous projections of future temperature and snow loss growth rates are overestimated across Asia. Therefore, the acceleration of future water cycles is expected to be slower. This has positive implications for climate mitigation and adaption.”

• The full study – Chai et al: Constrained CMIP6 projections indicate less warming and a slower increase in water availability across Asia – is published in Nature Communications, DOI 10.1038/s41467-022-31782-7.

The potential impacts of warming temperatures in Asia

As the Earth warms, Asia will experience increased heat stress, notably longer fire seasons and increased frequency and intensity of wildfires.

India is most vulnerable to health problems from heat exposure. China faces further desertification, soil erosion, dune mobilisation, sandstorms, and air pollution of its arid and semi-arid north-western regions. In certain regions of Asia, heat stress may lower crop production. Reduced water levels in some Asian rivers and lakes may damage fish populations, increase contamination levels, and promote the growth of algae (eutrophication).

For the Himalayas, higher temperatures will cause glacier retreat and less snow cover. Snowmelt and glacier water could significantly raise river flow discharges, increasing the likelihood of extreme floods and landslides which would inundate downstream cities, urban areas, and farmland. Several thousand glacier lakes are found in the Himalayas, comprising glacier meltwater enclosed by moraine. These lakes are susceptible to sudden outburst floods. In Nepal, snowmelt water may exacerbate floods, avalanches, and landslides, bringing a cascade of hazards to people living in downstream cities.

The study improves the accuracy of forecasts of temperature and precipitation growth rates over Asia, enabling authorities to develop better revegetation schemes, shelterbelts, flood mitigation measures, and flood warning systems. In short, it helps us better prepare for the challenges global warming is likely to pose to Asia.