Climate researchers from the National Centre for Atmospheric Science and the University of Reading have investigated the projected impacts of global warming on the Asian-Australian Monsoon region. The research shows that an additional 0.5°C increase in global warming is likely to increase the severity of climate impacts, including daily temperature extremes and rainfall intensity and frequency.

The study compared two scenarios, one where the world warmed 2°C beyond the pre-industrial average, and one where the world warmed by 1.5°C. This enabled researchers to quantify the impact that an additional warming of 0.5°C would have on (1) the mean temperature and rainfall patterns and (2) the frequency, intensity and persistence of temperature and rainfall extremes. The paper has been published in Earth’s Future.

RainInAsia 1000pxThe results of the study suggest that an additional warming of 0.5°C would cause an increase in regional surface temperature, and more frequent daily temperature and precipitation extremes over the Asian-Australian region. Limiting warming to 1.5°C could potentially reduce the risk of heat stress related impacts, including human health and spread of infectious diseases, crop yields over regions like India, stress in urbanised environments, and loss of ecological niches like coral reefs.

The study also projected increased monsoon rainfall in scenarios with an additional 0.5°C warming. An increase in the intensity and persistence of daily precipitation could escalate the risk of heavy floods in densely populated regions.

The research findings will help to inform future climate negotiations by providing evidence of the benefits of limiting global warming to 1.5°C. The Paris Agreement has focussed on strengthening mitigation efforts to limit the global temperature increase above pre-industrial conditions to 2°C, but there is a further target to limit global temperature increase to 1.5°C. So far there have been relatively few studies on the climate impacts of an additional 0.5°C temperature increase.

The researchers used data from climate models known as general circulation models. Such models simulate the earth’s atmosphere using mathematical equations. Model simulations were contributed by the Half a degree Additional warming, Prognosis and Projected Impacts (HAPPI) project, which provides a set of climate model outputs to be used to analyse the impact of 1.5°C and 2°C global warming on future worlds.

This research was supported by the UK‐China Research and Innovation Partnership Fund, through the Met Office Climate Science for Service Partnership (CSSP) China, as part of the Newton Fund. One of the co-authors was supported by an Independent Research Fellowship from the  Natural Environment Research Council (NERC).