Washington,

Scientists have presented new data from their analysis of ice core samples and ocean deposits dating as far back as 90,000 years ago and have suggested that warming, carbon dioxide levels and ocean currents are tightly inter-related.

Reconstructions of ancient atmospheric carbon dioxide (CO2) variations help us better understand how the global carbon cycle and climate are linked. We compared CO2 variations on millennial time scales between 20,000 and 90,000 years ago with an Antarctic temperature proxy and records of abrupt climate change in the Northern Hemisphere.

Sea levels have been determined for most of the Paleozoic Era (542 to 251 million years ago), but an integrated history of sea levels has remained unrealized. We reconstructed a history of sea-level fluctuations for the entire Paleozoic by using stratigraphic sections from pericratonic and cratonic basins.

Rising tropical sea surface temperatures alter atmospheric dynamics at heights of 16 kilometers or more.

The long-standing view of Earth

The concentration of atmospheric carbon dioxide decreased between
45 million and 25 million years ago, a trend accompanied by glaciation at the poles. Modelling results suggest when and where the ice closed in.

Human activity has increased the concentration of the earth's atmospheric carbon dioxide, which plays a direct role in contributing to global warming. Mid-tropospheric CO2 retrieved by the Atmospheric Infrared Sounder shows a substantial spatiotemporal variability that is supported by in situ aircraft measurements.

ALOK JHA

Carbon Diem' inventors claim that, by using GPS to measure the speed and pattern of movement, their algorithm can identify the mode of transport being used. It can therefore calculate the amount of carbon dioxide that a journey has emitted into the atmosphere

R K Pachauri re-elected head R K Pachauri was re-elected as chairman of the UN

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