There is growing public awareness that climate change will impact society not only through changes in mean temperatures and precipitation over the 21st century, but also in the occurrence of more pronounced extreme events, and more generally in natural variability in the Earth system.
There is growing public awareness that climate change will impact society not only through changes in mean temperatures and precipitation over the 21st century, but also in the occurrence of more pronounced extreme events, and more generally in natural variability in the Earth system. Such changes could also have large impacts on vulnerable ecosystems in both terrestrial and marine habitats. A scientific exploration of projected future changes in climate and ecosystem variability is described in a new study published in the journal Earth System Dynamics, representing the result of a broad collaborative partnership between the IBS Center for Climate Physics (ICCP) at Pusan National University in South Korea and the Community Earth System Model (CESM) project at the National Center for Atmospheric Research (NCAR) in the US.
The team conducted a set of 100 global Earth system model simulations over 1850-2100, working with a “business-as-usual” scenario for relatively strong emissions of greenhouse gases over the 21st century. The runs were given different initial conditions, and by virtue of the butterfly effect they were able to represent a broad envelope of possible climate states over 1850-2100, enabling sophisticated analyses of changes in the variability of the Earth system over time. The nominally one-degree (~100km) resolution of the model, in conjunction with the 100-member set of runs, represented an unprecedented set of technical challenges that needed to be met before advancing to the goal of assessing how climate variability is impacted by sustained anthropogenic changes to the climate system. “We met these challenges by using the IBS/ICCP supercomputer Aleph, one of Korea’s fastest supercomputers” says Dr. Sun-Seon Lee from the ICCP, a co-author of the study who ran the simulations together with her NCAR colleague Dr. Nan Rosenbloom. For the project, approximately 80 million hours of supercomputer time were used, and approximately 5 Petabytes of disc space (approximately 5000 normal hard discs) were required for storage of the model output.
The main finding of the study is that the impact of climate change is apparent in nearly all aspects of climate variability, ranging from temperature and precipitation extremes over land to increased number of fires in California, to changes in bloom amplitude for phytoplankton in the North Atlantic Ocean. Each of these changes has important impacts for sustainable resource management. As an example, occurrences of extreme precipitation events over the 21st century (between 2000-2009 and 2090-2099, see attached Fig. 1) indicate that extremes are expected to become more commonplace over many regions. These projected changes in precipitation extremes are in fact representative of the omnipresence of changes in extremes in the future across a broad range of climate and ecosystem variables, which has important implications for future adaptation strategies.
Read more at: Institute for Basic Science
Photo Credit: phtorxp via Pixabay
