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Summer Solstice

June 21, 2013 by · Comments Off on Summer Solstice 

Summer Solstice, The summer solstice occurs when the tilt of a planet’s semi-axis, in either the northern or the southern hemisphere, is most inclined toward the star (sun) that it orbits. Earth’s maximum axial tilt toward the sun is 23° 26′. This happens twice each year, at which times the sun reaches its highest position in the sky as seen from the north or the south pole.

The summer solstice occurs during a hemisphere’s summer. This is northern solstice in the northern hemisphere and the southern solstice in the southern hemisphere. Depending on the shift of the calendar, the summer solstice occurs some time between December 20 and December 23 each year in the southern hemisphere and between June 20 and June 22 in the northern hemisphere in reference to UTC.

Though the summer solstice is an instant in time, the term is also colloquially used like midsummer to refer to the day on which it occurs. The summer solstice occurs on the day that has the longest period of daylight – except in the polar regions, where daylight is continuous, from a few days to six months around the summer solstice.

Worldwide, interpretation of the event has varied among cultures, but most recognize the event in some way with holidays, festivals, and rituals around that time with themes of religion or fertility.

Solstice is derived from the Latin words sol (sun) and sistere (to stand still).

Summer Solstice, First Day of Summer

June 21, 2010 by · Comments Off on Summer Solstice, First Day of Summer 

Summer SolsticeSummer Solstice, First Day of Summer –Huffington Post — On June 21, the sun reaches its highest point in the sky, the summer solstice in the Northern Hemisphere, the longest day of the year. The summer solstice is like a giant celestial metronome, marking the arrival of the season and the passage of years with precise regularity. Mankind has celebrated monuments and built to date in the world and since time immemorial, the Neolithic culture of Stonehenge, the Mayans at Chichen Itza.

The solstice always keeps a steady pace, but in recent times, the pace of summer has been increasingly out of sync. When the climate warmed in recent decades, high temperatures arrived earlier on average, and a symphony of seasonal events with them, plant in bloom dates of migration of animals to achieve higher levels of flow in rivers fed by snow. Nowhere is this more evident than accelerating in the Arctic – the region most rapid warming of the planet.

One of the most dramatic changes on the surface of the Earth each year is the growth of winter and summer melt-back of Arctic sea ice – like a giant white flower opening and closing the top of the world. Based on satellite measurements taken over a base period of 1980-2000, the ice covering the Arctic Ocean beaches from a peak in late winter average of about 6 million square miles (more than twice the size of the 48 states), at least one type of late been much less than half that. The merger is growing by the summer solstice, every year when the average base-ice extent of about 4.6 million square miles.

But this year, according to NASA and the National Snow and Ice Data Center, the melting-back reaches that level in June 1, three weeks ago and since then has been at record levels for the period. This is particularly noteworthy because in April, stretches of ice per day hovered very close to the average baseline levels (as noted at the time by some commentators eager to suggest the world is not warming) . In other words, the ice retreated with exceptional speed in May – a speed close to the average rate of melting of July.

The record heat temperatures in the Northern Hemisphere this spring, recently announced by the National Climatic Data Center, and particularly in high latitudes, probably contributed to this rate. But more than weather this year is likely to play. It was widely reported that the coverage of Arctic sea ice has contracted in recent decades overall, for a month of your choice. It is least often mentioned as the sea ice has thinned over the same period – apparently faster than it fell in the region. It also seems to be large areas of “rotten” ice, filled with holes like Swiss cheese, where the satellite data did not distinguish between thick layers in strong health instead. Currently, an expedition led by NASA’s Arctic continues to investigate.

load of thin ice and rotten dice for the kind of ice retreat we see seasonal faster this year, and less Arctic sea ice coverage overall. This means that the ocean darker exposed to absorb heat from the sun for an extended period of time in a cycle that promotes further warming and melting Arctic.

But why should we take care of the frozen crust of an ocean away? The big question for Americans, as we move towards a national debate on energy policy and climate, is what comes after.

For this, we could look to Greenland, a sleeping giant of the Arctic, whose influence may extend all the way to our shores. Like melting ice does not change the level of water in a glass melting Arctic sea ice contributes essentially nothing to rising sea level, but when Greenland loses its ice on land in the ocean, it does raise the sea level – and Greenland has enough ice to make WinCE coastal city.

In other words, if the cycle is to increase the loss of Arctic ice and contributes to regional warming over the loss of Greenland ice, we would do well to pay special attention to the changing rhythms summer in the Arctic where they race ahead of the metronome solstice.

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