Earth and environmental scientists reported that as human socio-economic activities increase, greenhouse gas emissions will rise, leading to more frequent extreme weather events such as droughts and floods. However, a research team from Pohang University of Science and Technology (POSTECH) has published a study suggesting that anthropogenic greenhouse gases can actually alleviate droughts, offering a new perspective on the impact of human activities on nature.
Professor Jonghun Kam from the Department of Environmental Sciences and Engineering at POSTECH used climate model simulations to investigate the individual effects of aerosols and greenhouse gases produced by human activities, focusing on the 2022 spring drought that caused severe agricultural damage in the central mountainous region of the Andes . This research was recently published in the Bulletin of the American Meteorological Societyone of the international journals in the field of atmospheric science and meteorology.
Drought occurs when there is no rain for a long period of time, resulting in no precipitation. It starts as a meteorological drought and evolves into an agricultural drought where the soil loses moisture. More severe droughts can escalate into hydrological droughts, characterized by reduced stream flows. When droughts have a significant impact on society and the economy, they are called 'socio-economic droughts'.
The socio-economic consequences of drought are especially severe in societies and countries that are highly dependent on agriculture. During the globally severe spring drought of 2022, the central Andean mountain region of South America (including southern Peru, western Bolivia and northern Chile), where agriculture is a major industry, experienced greater economic difficulties than other regions . However, at that time, a shortage of human resources and funding limited the opportunity to better understand the causes of the 2022 drought.
In the study, Professor Jonghun Kam of POSTECH used eleven different climate models to analyze the impact of human activities on the spring drought that hit the central Andean region in 2022, the most severe since 1951.
Climate model experiments have shown that human socio-economic activities have increased anthropogenic aerosols in the atmosphere, affecting its chemical composition and exacerbating the spring drought in the central Andes. Conversely, increases in greenhouse gases due to human activities have increased precipitation in the region, mitigating extreme spring droughts and reducing the likelihood of such events. Aerosols and greenhouse gases resulting from human activities have thus had opposing effects on the chemical composition of the atmosphere and on precipitation mechanisms.
The study is important because it challenges previous conclusions that greenhouse gases are the main cause of drought in South Africa and Iran, highlighting the need for more extensive research into the effects of human socio-economic activities.
Professor Jonghun Kam said: “Some countries are disproportionately affected by extreme weather events due to the climate crisis, yet they often face a lack of not only human but also financial resources to respond proactively.” He added: “Our goal is to tackle the global climate crisis by conducting research that supports these countries and by thoroughly analyzing the impact of human activities on nature.”
The research was conducted with support from the Basic Research Program of the National Research Foundation of Korea.
