PALCOM International Focus Groups & Projects

During the 2019-2023 inter-congress period, PALCOM wishes to promote IFGs and projects which will (a) facilitate improved understanding of the climate system and the linkages across terrestrial, marine and glacial realms, (b) encourage large-scale syntheses of terrestrial data and the creation of palaeoclimate or palaeoenvironmental databases, and (c) foster improved links with the palaeoclimate modeling community.

IFGs are designed to address broad-scale questions and to provide an "umbrella" organization to facilitate communication between more focused projects. Individual projects should be linked to an IFG, except in the case of exploratory initiatives.

Informal queries about proposed IFGs and projects should be addressed, in the first instance by email, to the Commission President, Tom Johnson

INQUA IFG 2004F Terminations Five to Zero (T5-0)

Over the last ~450,000 years, the Earth went through five deglaciations, i.e. transitions from a glacial to an interglacial state, also termed “glacial terminations”. During these deglaciations, the concentration of atmospheric CO2, a powerful greenhouse gas, increased by 80 to 100 ppm and air temperature at high latitudes rose by 10 to 15 °C, leading to a melting of continental ice-sheets, thus raising global sea-level by 100 to 130 m. Deglaciations lasted about 10,000 years, but the changes did not occur gradually. Instead, they occurred in bursts lasting decades to centuries, and were usually associated with significant changes in oceanic circulation. While our understanding of these deglaciations has significantly improved over the last 20 years, the sequence of events that led to these deglaciations is still unclear. Particularly, there is a lack of information on the feedbacks linking the different components of the Earth’s system, i.e. the interaction between ice-sheets, climate, ocean circulation and carbon cycle. 

Due to anthropogenic emissions of carbon, the atmospheric CO2 concentration has increased to an unprecedented level of 415 ppm in 2019, from its “natural” interglacial level of 280ppm. This will undoubtedly have a large impact on the different components of the Earth System over the coming centuries, including melting of the Greenland and Antarctic ice sheets, and subsequent global sea-level rise. The knowledge gained from our understanding of the processes and feedbacks involved in the last five glacial terminations will help estimate the rate of future climate change. 

The goal of the IFG on Terminations 5-0 is to bring together scientists with different expertise (e.g. experts on marine and lake sediment records, ice core records, cave deposits, and sea-level with ice sheet, climate and carbon cycle modelers) to i) improve our understanding of the sequence of events occurring during the last five terminations, and ii) highlight key processes and feedbacks within the Earth system that lead to abrupt changes.

Contact: Ruza Ivanovic

Project 2005P : Glacial terminations: processes and feedbacks

Project 2005P details

PALCOM Other Related Projects

Project 1801P : Carbon in Peat on Earth Through Time: Tropical Peatland Processes and Ecosystem Services

Project 1801P details