Piteraq
The Piteraq (plural Piteqqat ) is a katabatic wind that develops on the Greenland ice sheet and then flows down the east coast. The word "Piteraq" means "He who attacks you" in Greenlandic. Piteqqat are most common in autumn and winter. Typical wind speeds are 50–80 m / s (180–288 km / h). On February 6, 1970, the Tasiilaq community was hit by the strongest documented Piteraq in Greenland. The estimated top speed was 90 m / s (324 km / h). The wind caused some storm damage. Piteraq warnings have been published by the Danish Meteorological Institute since the early 1970s .
Emergence
Piteqqat occur particularly in weather conditions when a low pressure area above the sea to the southeast of Greenland, the Irminger Sea, moves northwards. As the air over the up to three kilometers high ice over Greenland cools down considerably, it sinks and weighs on the land - a high forms, the natural opposite of the low on the sea. In a low air is sucked upwards, it acts like an outflow of the air masses of a high. Since the Greenland coast is very rugged by fjords , the outflow of the air mass increases - this is channeled into a narrow valley and breaks at the end of the fjord, where most of the few settlements are, like waves in a surf, which results in considerable acceleration Has. Whole ice masses can be driven from the fjord onto the open sea.
See also
Web links
Individual evidence
- ^ A b The Observed Climate of Greenland, 1958-99 , Danish Meteorological Institute , Technical Report 00-18, pp. 96-98.
- ^ Marilena Oltmanns: Strong wind events across Greenland's coast and their influence on the ice sheet, sea ice and ocean , Massachusetts Institute of Technology, 2012.