The question of how extreme weather events might be
linked to climate change is a key one.
It's particularly important because in many regions,
extreme weather like heatwaves, floods and droughts cause more
damage than other, more predictable consequences of climate change,
such as sea-level rise.
Scientists know that an increase in average
temperature as the climate changes will lead to an increase in
the number or magnitude of some extreme events, while others will
get less likely.
But the chaotic nature of weather means it's generally
impossible to say, for any particular event, that it only happened
because of climate change.
During the 2003 heatwave in Europe, summer
temperatures rose several degrees above those in 2000, 2001, 2002
and 2004. Image by Reto Stöckli, Robert Simmon and David Herring,
NASA Earth Observatory, based on data from the MODIS land
Probabilistic event attribution
On this basis, some people have concluded that it's
effectively impossible to attribute extreme weather events to
greenhouse gas emissions.
But this isn't quite right, and there are ways we can
explore the links.
My colleagues and I work on the emerging science
Probabilistic Event Attribution (PEA), which tries
assess how much human-induced climate change is
affecting local weather events such as