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Whether cooling occurred in the Southern Hemisphere during the Younger Dryas (YD) is key to understanding mechanisms of millennial climate change. Although Southern Hemisphere records do not reveal a distinct climate reversal during the late glacial period, many mountain glaciers readvanced. We show that the Puerto Bandera moraine (5005), which records a readvance of the Southern Patagonian Icefield (SPI), formed at, or shortly after, the end of the YD. The exposure age (10.8 ± 0.5 thousand years ago) is contemporaneous with the highest shoreline of Lago Cardiel (49°S), which records peak precipitation east of the Andes since 13 thousand years ago. Absent similar moraines west of the Andes, these data indicate an SPI response to increased amounts of easterly-sourced precipitation—reflecting changes in the Southern Westerly circulation—rather than regional cooling. [ABSTRACT FROM AUTHOR]

The article discusses the causes of glacial cycle in earth. It has been stated according to the Milankovitch theory that the changes of insolation is the cause of ice age cycle. Insolation is described as the exposure of the earth's surface to the rays of the sun. It varies on time scales of thousands of years as a result of regular changes in earth's orbit around the sun, in the tilt of earth's axis, and in the direction of earths axis of rotation. An example has been cited that between 3 and 1 million years before present, glacial oscillations follows a 41,000-year cycle and that these oscillations correspond to insolation changes driven by obliquity changes. Other information related to the topic are discoursed in the paper.

The article focuses on the deglaciation during Pleistocene epoch. A compiled evidence suggests that the sea levels would fluctuate by 30 to 40 meters during the start of warm intervals. This occurrence will confirm the variability of relative elevations of deposits in Greek shoreline. Information to determine the sample ages using U/Th dating found out that the sea level will drop twice precipitously between 136,000 and 135, 000 years in Red Sea and Papua, New Guinea. These results will constrain the timing of sea-level rise during the penultimate deglaciation.

This article presents views of paleoclimatologists about Earth's climate. Indeed, the revival of the Snowball Earth hypothesis almost 7 years ago has bogged down of late, as paleoclimatologists have failed to turn up unequivocal evidence that ice enrobed the planet. A group of geochemists offers a new snowball marker: the element iridium, which continually rains down on us from space. They say they found so much iridium deposited at the end of a glaciation 635 million years ago that the planet must have been frozen pretty much solid for 12 million years straight.