Lonnie Thompson is University Distinguished Professor at Ohio State University in the School of Earth Sciences and the Byrd Polar Research Center. He is the leading paleo-scientist who drilled and preserved ice cores from high mountain glaciers while others focussed on Greenland and Antarctica.
In 1952 the Danish geophysicist Willi Dansgaard made a discovery that opened up a completely new field of research. He found that the amount of heavy oxygen isotopes in rain correlates with the temperature at the location where the precipitation was formed. But more important in preparation for debates with climate change deniers is the record of CO2 that is also preserved in the ice cores. The correlation of temperature rise and decrease with increasing and decreasing CO2 and methane content have become one of the most important proofs for climate change. Ice cores also show the recent extraordinary increase in the amount of CO2 since the industrial revolution and the ever escalating burning of fossil fuels.
Today ice core records exist going back 800,000 years for Antarctica and 123,000 years for Greenland. They show that never in those 800,000 years have the concentrations of CO2 been as high and rising as rapidly as today.
Thompson was undeterred by the doubts expressed by his teachers and mentors. Willi Dansgaard told him that human beings were physically unable to do ice core drilling at altitudes of 18,000 plus feet, that no equipment existed that could be brought to the tops of the inland glaciers and that it would be extremely difficult to get the ice cores down the mountain before they melted.
Thompson and his team built a solar powered ice core drill and have now retrieved cores in 16 countries on 61 expeditions. This collection is priceless because nobody will ever be able to duplicate his work because over 90% of the glaciers he worked on are melting.
Lonnie Thompson was interviewed by the University of Queensland, Australia, Making Sense of Climate Change Denial project. They are an international team presenting interviews on their YouTube channel that bring information to the public to help deal with the arguments of the climate change deniers.