Rockall part of the deeply eroded Rockall Igneous Centre that was formed as part of the North Atlantic Igneous Province, approximately 55 million years ago, when the ancient continent of Laurasia was split apart by plate tectonics. Greenland and Europe separated and the northeast Atlantic Ocean was formed between them, eventually leaving Rockall as an isolated islet. The RV "Celtic Explorer" surveyed the Rockall Bank in 2003. The Irish Light Vessel "Granuaile" (the same name as the steamer on the RIA 1896 botany survey) was chartered by the Geological Survey of Ireland, on behalf of the Department of Communications, Marine and
Monsoon trough surge has reached a monsoon trough is the formation of a burst of thunderstorms within the monsoon trough. If a circulation forms within the monsoon trough, it is able to compete with the neighboring thermal low over the continent, and a wind surge will occur at its periphery. Such a circulation which is broad in nature within a monsoon trough is known as a monsoon depression. In the Northern Hemisphere, monsoon depressions are generally asymmetric, and tend to have their strongest winds on their eastern periphery. Light and variable winds cover a large area near their center, while bands of