“The melting of the ice on Greenland is significant!”
By Dr. John J. Hidore
There is no doubt that Planet Earth is warming relatively fast. Data of all kinds supports this allegation. The data include biological, geological, hydrological and climatological. The year 1880 has been established as the beginning of a period of accelerated warming due to the increased use of fossil fuels and a growing population. From 1880 to 1979, the global temperature increased 0.1°F (0.05ºC) above the pre-industrial average. By 2016, the global temperature had climbed 1.4°F(0.6ºC).
Melting of the Arctic Sea Ice
Northern Hemisphere is Warming Faster than the Southern
Climate normals are periods of 30 years that move forward every 10 years. The current normal being used is that of the period 1980-2010. When compared to the 30 year global average for the period 1980-2010, the northern hemisphere is warming faster than the average for the earth as a whole. It is also warming faster than the southern hemisphere. The reason the Northern Hemisphere is warming faster than the southern Hemisphere is due to the fact that most of the earth’s land mass is in the Northern Hemisphere.
The exchange of energy is causing rapid arctic melting.
The Arctic Region is the Most Rapidly Warming Region in the Northern Hemisphere
The Arctic is the coldest region in the Northern Hemisphere. The region consists of the sea surrounding the North Pole and land that rings the sea. The arctic is warming faster than mid-latitude or tropical regions. It is warming more than twice as fast as the average for the earth. The reason for this is, as ice and snow melt on the fringes of the arctic, the ratio between reflection and absorption of solar energy changes drastically. In the winter the sea is covered by a veneer of ice and the surrounding land is generally covered by snow. With the onset of summer the increased solar radiation results in the melting of the ice and the snow melting off the land. The more snow and ice that melts, the faster the arctic warms. This change results in what is known as a positive feedback mechanism. More and more energy is absorbed rather than reflected or used to melt the ice. As the melting season lengthens the land and atmosphere above it warm faster than areas further south. While the Arctic is still the coldest region in the Northern Hemisphere, it is warming more rapidly than other areas.
Climate Change is altering the World’s largest Island
Greenland has the most extensive ice cover of any island on the planet. In much of the region the ice is more than a mile ( O.6 km) thick. The melting of the ice sheet has been monitored by satellite since 1979. The ice sheet normally starts to melt at the end of May. In 2016 the ice began to melt in mid-April. The higher temperatures resulted in early melting of the ice sheet. In the second week of June there was melting over nearly half of the ice surface. This was a record area of melting for this date. Part of the reason for the extensive melting this year was the light snow cover during the past winter. It melted fairly quickly allowing the sunshine and warmer air to increase melting in the older snow and ice beneath. How much melting occurs on any given day depends on wind direction and cloud cover.
The year of 2012 was the record year for total melting of the ice sheet. The town of Narsarsuaq recorded a temperature of 76.6°F. In that year there was a net loss of some 200 billion tons of ice.
Climate Change Affects Everyone!
Selected High Temperatures
2012 Marsarsuaq May 76.6 °F
2013 Manitsoq July 78.6 °F
2014 Kangerlussuaq Jan 73.8°F
2016 Nuwk June 75 °F
Spring temperatures came early to the Arctic this year. The island of Greenland experienced these early warm temperatures. Average temperatures exceeded normal by several weeks. In some areas the temperatures were as much as 40° F (22°C) above normal. The early warm temperatures have resulted in early and extensive melting of the ice sheet.
The melting of the ice on Greenland is significant because it is the major source of water for the current rise in sea level. If all the ice melted it is estimated that it would raise sea level approximately 24 feet (7.3 meters). Since data has been collected, in the early 1970’s, sea level has risen about ½ inch (1 ¼ centimeters).
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