ACE: Antarctic Climate Evolution

Fig 1 Recent geological and glaciological field activities in Antarctica, illustrating the variety and spatial extent of existing and forthcoming datasets useful to the ACEprogramme.

Fig 2 Variation in the Earth's temperature during the last 65 million years, based on reconstructions fromdeep-marine oxygen isotope records. Note the general cooling trend from 50 million years ago. Also note the abrupt "climatic threshold events". For example ~35 million years ago when abrupt global cooling led to the first ice sheets developing on Antarctica. Future atmospheric temperature scenarios are based on IPCCgreenhouse trace gas projections are shown at top of diagram. Given the worse case scenario, planetarytemperatures could increase in 100-300 years to a level where, according to our knowledge of previousAntarctic glaciations, ice cover on Antarctica could not be sustained.

ACE is a Scientific Research Programme of the Scientific Committee on Antarctic Research(SCAR).The purpose of ACE is to study the climate and glacial history of Antarctica throughpalaeoclimate and ice-sheet modellinginvestigations, integrated with geologicalevidence for past changes.

The ACE programme aims to facilitate research in the broad area of Antarctic climate evolution.The programme will link geophysical surveysand geological studies on and around the Antarctic continent with ice-sheet and climate modelling studies.These studies are designed toinvestigate climate and ice sheet behaviour in both the recent and distant geologic past, including times when global temperature wasseveral degrees warmer than today.

ACE has produced a series of four special scientific issues;

Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 198 (2003)Global and Planetary Change, vol. 45 (2005)Palaeogeography, Palaeoclimatology, Palaeoecology, vol 231 (2006)Palaeogeography, Palaeoclimatology, Palaeoecology (in press 2008)

ACE has also compiled a book entitled Antarctic Climate Evolution, published by Elsevier in October 2008.

ACE has had formal Scientific Research Programme status from SCAR since October 2004.

The five main functions of ACE are as follows:

1. encouraging and facilitating communication and collaboration between research scientists working on any aspect of the evolution of Antarctic climate. This would be achieved by organizing workshops and symposia to present new results, exchange ideas, share/compile information and coordinate/plan laboratory and field operations. These would be coordinated with the activities of autonomous programmes such as ANDRILL, IODP and SALE (another SCAR SRP), and designed to complement them;

2. advising the research community on the types of geoscience data required for the palaeoclimate models, and the likely sampling locations to acquire such data;

3. providing advice/assistance as needed on technical issues related to geoscience field and laboratory programs and to palaeoclimate modelling studies;

4. promoting data access and data sharing (and data-contributions to the SDLS and Antarctic data centres) to facilitate and expedite data syntheses needed for developing new field programs and enhancing palaeoclimate models. This function includes direct guidance of the ATCM-mandated SDLS.

ACE coordinates the acquisition and compilation of "ground truth"geoscience data from geophysical surveys and drilling, and the use of these data in developing a suite of palaeoclimate models (bothcontinent-wide and sectorial) for the Antarctic region for significantperiods of climate change through Cainozoic times.These periodsinclude:

Late Eocene-early Oligocene cooling

Middle-late Miocene cooling

Pliocene warm periods

Pliocene-Pleistocene cooling

Quaternary warm periods

Warming since the Last Glacial Maximum

Holocene "stable" period

www.ace.scar.org