Sediments from Lake Meerfelder Maar in Germany shows the transition from the Allerød warm phase into the cold Younger Dryas period. Lake varves, tree rings, and ice cores all record past climate conditions year by year.
Seeds can be found in lake and peat cores. By knowing the requirements of the plants alive today, seed assemblages can tell us about past vegetation, environment, and climate conditions in the vicinity of the sampling site.
Ocean sediments are sampled using heavy equipment on specialized research vessels. The cores are used to reconstruct past times’ ocean temperatures and circulation conditions.
Ice cores drilled from the Greenland and Antarctic ice caps contain layers of old snow that are analysed in order to reconstruct past atmospheric conditions more than 100,000 years back in time.
Lake sediments provide detailed and highly resolved information on past local and regional climate conditions. Careful dating and analysis of sediments from many such locations paint a detailed picture of the climate of the past.
Geochemical analysis of dripstones sampled from caves is applied to investigate the climatic and environmental variability on many different time scales.
The strength of the ocean circulation in the North Atlantic has a strong impact on the climate of the surrounding areas. In return, the amount of sea and land ice and melt water from land-based ice influence the North Atlantic circulation.
Ice cores are analysed in many different ways: the stable water isotopes reveal past temperatures, acidity pinpoints volcanic layers, and impurities in the ice are tracers of e.g. forest fires and dust storms.
Lake Suigetsu in Japan contains annually layered sediment reaching 70,000 years back in time that has the potential for both climate reconstructions as well as extending the terrestrial 14C calibration curve.
Volcanic ash particles (tephras) sampled near the source and geochemical fingerprinting of the tephra makes it possible to relate volcanic layers found in sediments to specific volcanic eruptions.
This mammoth tusk found at a construction site in Switzerland was dated to over 45 ka BP by Accelerator Mass Spectrometry (AMS) 14C dating. Past climate conditions are reconstructed using this type of finds.
Microscopic algae remains, for example from diatoms, are identified in lake sediment cores to reconstruct past environmental changes; especially temperature, nutrients, or lake acidity.
Drilling and analysis of ice cores take place in trenches cut into the ice sheet. In this way, the ice cores laboratories are kept cold and the amount of building materials is minimized.
Climate modeling plays an important role in the INTIMATE project, adding to our understanding of the processes that governed past climate and the interpretation of palaeoclimate data.
The polar planktonic foraminifer Neogloboquadrina pachyderma sinistral is abundant in the polar waters around Greenland and in the Arctic Ocean today, but was found as far south as 40°N during glacial periods.
The objective of INTIMATE is to reconstruct past abrupt and extreme climate changes over the period 60,000 to 8000 years ago, by facilitating INTegration of Ice core, MArine, and TErrestrial palaeoclimate records and using the combined data in climate models to better understand the mechanisms and impact of change, thereby reducing the uncertainty of future prediction.
The project is organized in 4 working groups:
|Working Group 1 – Dating and Chronological Modelling
A reliable chronological framework is the basis of all studies of the past climate. WG1 is dedicated to developing and improving dating methods over the last 60,000 years and bringing scientists together to develop a coherent dating framework in which records can be compared at unprecedented detail.
|Working Group 2 – Quantification of Past Climate
The aim of WG2 is to collect and quantify information of past climate from e.g. ice cores, tree rings, corals, stalagmites, and marine and lake sediments in order to draw a detailed picture of the highly variable climate evolution in the North Atlantic region.
|Working Group 3 – Modelling Mechanisms of Past Change
Our ability to forecast the rates and magnitudes of future change depends on numerical models. By using combined ice core, terrestrial, and marine data sets as targets, WG3 will optimize methodologies to evaluate model simulations and make data-model comparisons.
|Working Group 4 – Climate Impacts
The group will gain insights into the impacts of past climatic changes on animal and human populations and the ecosystems of which they are part. WG4 will quantify the magnitudes and rates of population, species, and ecosystem responses in space and through time.