Lonnie Thompson conveniently in Dunedin

We’ve been to two Lonnie Thompson and Ellen Mosley-Thompson talks this week.    I was very impressed. 

The first “Climate change: past present and future” was an overview of their thirty years of research into icecores.  

The talk took an interesting approach.  Thompson didn’t muck around.  Two slides at the start cover the contributing factors (natural and anthropogenic forcings) and the timescales they operate on.  Then he launched into masses upon masses of evidence of climate change from the ice core record.  He talks about his focus on tropical glaciers where climate change will have the greatest adverse impact and most people , drives the climate, and, coincidentally has the best record because of the seasonal effect in the cores.  About halfway through he switched from graphs to comparison images of (disappearing) glaciers .    The summary is that the changes in the ice we see now are “unprecedented for 1000s of years”.   He says that we are already committed to the loss of mountain glaciers.  

we are in unfamiliar territory, the world’s ice cover is responding dramatically

Thompson argues that we have 

a perfect storm brewing of 1000 year C02 lifetime, climate system inertia, positive feedback and our fossil fuel addiction. 

I enjoyed the glimpses of science as a  human endeavour.  The notion of getting huge amounts of equipment to the most inaccessible places on earth and back again is such a massive undertaking.  When I ran our Regional Council’s soil and vegetation monitoring programme the cost of acquiring data meant we treated it like gold dust.  The cost of the Thompson’s data must be several orders of magnitude greater.   I especially enjoyed images of yaks carrying boxes of ice. 

The question Thompson asks is whether we are at a tipping point, a perhaps catastrophic abrupt change.  He points to such an abrupt change 5,200 years ago.  He suggests that there are connections to changes in civilisation (ie the simultaneous invention of calendars in three continents and a switch to agriculture).  Later on he asks what sort of crisis will it take for us to make real changes.  I’d like to see this explored more.  

In questioning, Thompson was asked about the most important lifestyle changes we should engage with.   He points to initiatives such as Salt Lake City.    Hugh Bennett’s development of soil conservation in the 1930s could be a precedent.