One of the biggest threats to our agriculture, and also to the survival of ecosystems, is drought. The scarcity of water in a territory occurs when a land experiences lack of rain for a considerable period. And, like many meteorological processes on our planet, it is closely related to climate change. While droughts can be seasonal, or even endemic to a dry region of the planet, some regions of the Earth are experiencing unusual and worrying desertification as a result of global warming.
Droughts, –which put the planet’s food health at risk, and could cause great famines, movements of climatic refugees and the disappearance of species– could become increasingly intense and frequent in the future , according to a climate model published in the journal Geophysical Research Letters by a team of researchers from the ARC Center of Excellence for Extreme Climates.
As they explain in a statement from the center itself, quantifying how climate change drives drought is a priority in order to plan adaptation policies in agriculture, water security and ecosystem management.
What regions will be most affected?
In the research, regional drought patterns were studied for two high-emission scenarios up to the year 2100. The results showed very unflattering results for several regions of our planet: Australia, the Amazon, the Mediterranean and southern Africa will experience droughts more frequent and intense throughout this century. What’s more, while some regions, such as central Europe, are expected to get humid and suffer less from water scarcity, even these areas can expect more intense droughts as rainfall becomes more variable.
Overall, the projection of this team of experts foresees robust changes in the frequency and duration of seasonal meteorological drought in more than 45% of the global land area.
“We found that the new models produced the strongest results for future droughts to date and that the degree of increase in the duration and intensity of the drought was directly related to the amount of greenhouse gases emitted into the atmosphere,” in words from the lead author, Dr. Anna Ukkola. “There were only slight changes in the drought areas in a mid-range emissions scenario versus a high emissions pathway. However, the change in the magnitude of the drought with a higher emissions scenario was more marked, which tells us that early mitigation of greenhouse gases is important, “he adds.
Are we in time to avoid it?
These projections provide direction in planning water resources and identifying agricultural and natural ecosystems at risk. Anticipating catastrophic scenarios has its positive side: it allows us to anticipate ourselves. But the main action that countries must take, beyond adaptation, is mitigation. As we have mentioned, these predictions are given for high emissions scenarios; But reducing the amount of greenhouse gases could lessen (to a greater or lesser extent) the effects that these droughts could have on our planet, to try to make them less disastrous : “However, although these ideas become clearer with each advance , the message they convey remains the same: the sooner we act to reduce our emissions, the less economic and social pain we will face in the future, “the article was quoted as saying.
The results of the ARC Center of Excellence for Extreme Climates will be released before the next evaluation report of the IPCC (Panel of Experts on Climate Change).
Referencias:
Ukkola, A. M., De Kauwe, M. G., Roderick, M. L., Abramowitz, G., & Pitman, A. J.. ( 2020). ‘Robust future changes in meteorological drought in CMIP6 projections despite uncertainty in precipitation’. Geophysical Research Letters, 47, e2020GL087820. https://doi.org/10.1029/2020GL087820
