In 2015, to combat the urgent threats posed by climate change, most of the world’s countries came together to establish the Paris Agreement: an ambitious plan to prevent the global temperature from rising 2°C above pre-industrial levels, and to work to further limit that temperature rise to 1.5°C.

These seemingly small numbers can mask the staggering impact and complexity that shifts in global temperature represent. For example, increased global temperature will also intensify the hydrologic cycle, significantly changing the frequency and intensity of rainfall. Flooding, droughts, mudslides, and food and water insecurity are just some of the many hazards of the resulting changes in rainfall patterns.

To understand what the future may hold, and to shape policies and behaviors that guide this outcome, researchers at The University of Tokyo, along with international collaborators, have developed a new metric for evaluating the intensification of wet and dry spells under the effects of global warming. They call it the “event-to-event hydrological intensification index,” or E2E, as described in a new study published in Scientific Reports.

“The E2E combines normalized aggregated precipitation intensity and dry spell length to capture the interconnectivity of adjacent dry and wet spells and the intensification of their phase shifts,” explains corresponding author Hyungjun Kim.

Source: Half a degree more warming may cause dramatic differences on drought-flood compound risks