Professor Wyss Yim: Geothermal Heat and Climate Variability
Geothermal heat released through terrestrial and submarine volcanism is an underestimated cause of natural climate variability. Satellites since the early 1980s and ARGO ocean profiling floats since the early 2000s are providing observational records that enable us to study the influence of geothermal heat on climate. Volcanic eruptions can be the cause of both cooling and warming of the atmosphere and the hydrosphere in addition to causing extreme weather events. During large terrestrial eruptions, high plumes inject ash and sulphur-rich particles into the troposphere and stratosphere causing warming initially followed later by cooling. They also release large amounts of carbon dioxide. Lava flows into oceans warm the seawater below the surface. Case studies will be used to highlight the role of geothermal heat on climate variability including the 2014-2015 ENSO and Arctic sea ice changes during the past decade.