EARTH’S CLIMATE HISTORY AS RECORDED IN GLACIERS AND ICE CAPS ON THE WORLD’S HIGHEST MOUNTAINS

Over the last 36 years we and our colleagues have conducted expeditions in 16 countries to recover ice cores from the Himalayas, the Andes, Kilimanjaro, New Guinea, Russian Arctic, Alaska, Antarctica and Greenland to document and understand Earth’s rapidly changing climate system. These field projects required enduring harsh conditions, living for months in very remote locations far from the basic comforts we take for granted such as warmth, cleanliness, easily available food and communications with those at home. Personal experience confirms that although the mountainous terrain ahead may seem daunting at times, but it is in meeting and overcoming hardships that we directly confront our strengths and weaknesses, beliefs and fundamental values.

As our ability to explore remote areas has improved and glaciology has matured as a science. Both have played a vital role in the development of the field of tropical paleoclimatology. The lecture will share some of the adventures linked to the development of the field of tropical paleoclimatology from the early days when the first solar powered drilling system was used to recover the first tropical ice cores from the Quelccaya ice cap in the Andes. This was followed by the thrill of drilling the first ice core on the Tibetan Plateau, discovering glacial stage ice preserved on Huascarán located just 9 ^oS of the Equator and drilling cores from the rapid shrinking ice fields of Papua, Indonesia. I will share a few lessons I have learned while climbing my mountains, both real and symbolic.

Our world is changing faster than at any time in our history and it’s difficult to know what the future will hold. This year carbon dioxide levels exceeded 400 ppm at Mauna Loa where David Keeling first measured CO₂ in the late fifties. The concentration then was 317 ppm. Concentrations today are the highest in the last 3 million years (mid-Pliocene) and at that time temperatures were 2-3 °C warmer than today and sea level was roughly 25 meters higher.

For global climate change Nature is the timekeeper and unfortunately none of us can see the clock, but we do know that it is ticking. In the end we all have to deal with reality and determining what is real requires us to face the problem, gather real data, and work together as a nation in concert with other countries to develop viable solutions and implement them.