ESA study showed that the Arctic sea ice measured last October 1, 50% in volume over the previous year, according to data obtained from the CryoSat satellite.
“It’s good news,” said a researcher RTVE.es in oceanographic remote sensing of the Spanish Institute of Oceanography (IEO), Carlos Garcia-Soto, who not rule out that the trend will reverse in 2014 according to the trends observed since 1979.
Climate change caused by humans
researcher has pointed out, moreover, that the average of the last three decades have been warmer than the previous decades since 1880, when it began to be measured temperatures. He adds that “there is a general consensus that this is anthropogenic climate change”, ie Man caused.
There is widespread consensus that climate change is anthropogenic
García-Soto believes that to mitigate climate change should reduce emissions of carbon dioxide (CO2) , but in general, the international community “is not implementing policies decided to reduce it.”
“We have opted for adaptation policies rather than policies and mitigation, but adaptation policies can not be implemented by developing countries with limited financial resources where further climate impacts will be greater, for example in Africa, “he stressed.
IEO researcher has emphasized that understanding of climate change is based on trends or variability of long term and not on variations from one year to the next. In chapter book Blue Planet. Oceans and Society (Blue Planet. Oceans and Society), which is an author, discusses some satellite measurements of global warming, its impact on the ocean and rising global sea level.
Son conclusions are in line with the fifth study on climate change by the Intergovernmental Panel on Climate Change to be presented in September.
global temperature anomalies
The study shows that the overall increase temperature has occurred because of the increased concentration of greenhouse gases, which is known as climate change.
Garcia-Soto collected and analyzed data collected by NASA satellites, ocean buoys, research stations in Antarctica and ambient temperature of about a thousand meteorological stations between 1880 and 2010.
The main conclusion is that global temperature has increased about 0.85 ° C since 1900, and nearly 60% of the increase has occurred since 1980 .
According to reports from the Goddard Institute for Space Studies (GISS), nine of the ten warmest years have occurred since 2000.
The warmest year was 2010 , although there was a transition of Hurricane El Niño to La Niña in the Pacific, a factor of global cooling.
About the hurricanes, more intense and violent Garcia-Soto explained that there are studies for and against their relationship to climate change although he considered more than likely this relationship.
sea level rise
Another object of study are expert IEO platforms Antarctic sea ice aa near the coast and with a thickness of between 50 and 600 meters. Antarctica remain immense ice shelves 15 , some of which are disintegrating, especially in the Antarctic Peninsula.
Some of the huge blocks of ice in Antarctica are disintegrating
disintegration of the ice blocks has also occurred in the Arctic, although with less intensity than in the southern hemisphere. Garcia-Soto melting points of the blocks in the northern hemisphere has no significant direct effect on sea level , since both components of the cryosphere are already located in the ocean.
However, the researcher notes that this disintegration is accelerating the rate at which glaciers flowing into the ocean. And home ice, which is melting, is a major cause of rising sea level.
sea level rise from melting glaciers, among other things
instruments like altimeters have allowed measuring sea level in the last 20 years in all oceans, and these data show that the average overall increase since 1993 has been between 2.6 and 3, . 8 mm per year
The causes mentioned by Garcia-Soto, in order of importance are: ocean warming, increasing the volume of water or termostérico-effect, the melting of glaciers -mainly small-mountain glaciers, melting of Greenland and Antarctic ice shelves, including its effect on Antarctic glaciers-and land-water contribution a variable effect.
The study reports that the sea level rise varies by region, as demonstrated by satellite measurements. This is higher in the western than the east Pacific. In the Mediterranean sea or Black sea, two semi-enclosed seas, the linear increase is less clear, since they appear more cyclical variations.
Arctic to global warming
higher temperature anomalies recorded in the Arctic . In this region, the loss of ice due to the increase in temperature causes the reduction of solar radiation that is reflected increasing the absorption of solar heat in a feedback effect or feedback .
The extent of Arctic sea ice has shrunk so “drastic” between 1979 and 2012, an average of 0.94 million square kilometers per year, or an extension -11.5% per decade.
extension minimum Arctic sea ice recorded in September 2012 , when they fell to a record 3.53 million km2. This represents a decrease of approximately 45% compared to the average of the base period 1981-2010 (6.5 million km2). Have also been detected lows in 2002, 2005, 2007 and 2012 (data from NSIDC).
Another consequence of climate change in the Arctic is that spring thaw begins and ends before more later . Particular has increased six days a decade. The Arctic ice thickness has also been reduced by 25% per decade, rising from 3.64 meters to 1.89 meters 1980 2008“The EU and the OECD. – among others-are seeing potential for exploitation of mineral and petroleum resources in the Arctic, but still think it’s a tragedy, “Garcia-Soto finished.
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