A study has found that extreme precipitation events around the globe including flooding and landslides were influenced by human activities, such as greenhouse gas emissions and land use change.
Attribution research studies aim to better understand whether human actions that impact the climate contribute to the occurrence and severity of extreme weather events. One such study, published on 6 July in academic journal Nature Communications, saw University of California, Los Angeles (UCLA) researchers look at global climate records to determine whether human-influenced changes to the climate had affected extreme precipitation.
The researchers were able to find evidence to support the notion that human activity had affected extreme precipitation by looking at several sets of observed precipitation data to build a holistic understanding of the global climate. Work in this field has usually been restricted to specific countries instead of being applied globally, but the UCLA research team made use of machine learning to generate a global data set.
Lead researcher Gavin Madakumbura said that it is ‘vital to identify the changes caused by human action, compared to the changes caused by natural climate variability’, and that this would allow for the management of ‘water resources and plan adaption measures to changes driven by climate change’.
The Earth’s temperature is rising as a result of human-induced climate change, with different mechanisms linking higher temperatures to extreme weather and precipitation. According to Madakumbura, ‘The dominant mechanism [influencing extreme precipitation] for most regions around the world is that warmer air can hold more water vapour’ which ‘fuels storms’.
Data from the Meteorological Office shows that intense rainfall is increasing globally, with the rainiest days of the year yielding higher levels of precipitation. Heavy rainfall days also pose a problem, as short, intense bursts of rain can result in flash flooding which can severely damage infrastructure and the environment.
Dr. Sihan Li, a senior research associate at the University of Oxford who was not involved in the study led by Madakumbura, noted that ‘We are already observing a 1.2C warming compared to pre-industrial levels’. Li went on to add that ‘If warming continues to increase, we will get more intense episodes of extreme precipitation, but also extreme drought events as well’.