Saturday, September 28, 2013

As climate change alters the Earth - Hamburg Evening Gazette

class=”topLine Time”> 28/09/13, 02:20

More heat waves, a fast rising sea levels – the IPCC warns in his new report from the effects of global warming

Stockholm. How global warming could evolve in the future? In search of answers 259 lead authors from 39 countries have seen thousands of studies over the past four years, supported by more than 600 other researchers. Now the first part of the fifth report of the UN IPCC as to the physical condition of our planet is ready. The factory covers about 2000 pages, the summary of the policy is 36 pages. Résumé this, the Council decided on Friday in Stockholm. The full report will appear on Monday.

instructions for action are not the IPCC, the body will only represent the state of research on climate change. What conclusions does the policy decides to climate conferences. The next one is scheduled for November in Warsaw.

In the second and third part of the most recent IPCC report discusses the impact of climate change and policy options to curb global warming. You will be presented in spring 2014 in Japan and Berlin.

now presented in the first part of the global research collaboration comes to the conclusion that climate change proceeds unchecked. The most recent assumptions about global warming, rising sea levels and the melting of glaciers keep the scientists safer than ever before. “There are many acquisition systems, satellites, and more new instruments, so you can capture the entire climate system better,” said Ulrich Cubasch of the Free University of Berlin, one of the lead authors.

The main results at a glance:

greenhouse gases and global warming

The concentration of carbon dioxide (CO2) has increased by 40 percent since the beginning of industrialization. Reasons are mainly the burning of fossil fuels. According to the report, the concentration of the greenhouse gas methane rose by 150 percent, the. Nitrous oxide by 20 percent CO2 is the largest contributor to the greenhouse effect and thus contributes to global warming, but other gases in the atmosphere are involved in it (see box).

If the temperature increases by more than two degrees above pre-industrial era scientists fear uncontrollable environmental consequences. For example, the risk of floods, droughts and storms would rise. Therefore, the international community had agreed in principle to work on a new global climate agreement that will stand until 2015 that the tide of global warming to two degrees must be limited to the year 2100

Can this be achieved? In the most recent IPCC report, the researchers involved are based on four scenarios of CO2 emissions. On this basis they calculated the possible temperature rise. Accordingly, the average temperature would increase by a from 0.3 to 4.8 degrees and 2100. This confirms roughly what the researchers had predicted in its fourth report of 2007. The values, however, each must be considered that the average temperature above pre-industrial era has already risen by about 0.8 degrees. With only the lowest two scenarios would be considered as critical under the two-degree mark.

Never since the beginning of records, it was the most recent IPCC report, the warmer than in the first decade of the 21st Century. “There are more temperature records have been broken than in any other decade,” said the Secretary General of the World Meteorological Organization WMO, Michel Jarraud.


heat waves and heavy rain

During the warming heat waves could very likely occur more often. In the mid-latitudes and tropical regions are likely to be more severe and heavy rains occur more often. Already in high rainfall areas, there is probably more rain, less in dry areas – Exceptions are possible

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oceans and ice

The rate of ice melt from Greenland and Antarctica has multiplied according to the report. It is very likely that the Arctic ice continues to decline. The oceans have absorbed 90 percent of the energy that is stored in the last few decades the climate system. They warmed up from 1971 to 2010 in up to 75 meters depth about 0.1 degrees per decade.

The melting of glaciers and the thermal expansion of the oceans has risen by 19 centimeters of sea level from 1901 to 2010. In the future, this process could accelerate: “While heating the oceans and melting glaciers and ice sheets, global sea level will continue to rise, but faster than we have seen in the last 40 years,” said Qin Dahe, one of the co-chairs the IPCC. In most climate efforts in sea level would therefore likely increase until the end of the century (2080-2100) by 26 centimeters by 82 centimeters in the worst case. Looking at just the year 2100, it could even be up to 98 centimeters. In its 2007 report, the IPCC had predicted increases from 18 to 59 centimeters. “The last report to the sea still missing data,” said Ulrich Cubasch of the Freie Universität Berlin. “Now they have found new techniques to estimate the. This is a major contribution, and therefore the numbers have also become higher.”


influence of man

The 2007 report stated there that mankind global warming is “very likely” mitverursache. This portion of mankind figured the researchers with more than 50 percent. Now the IPCC is “in all probability” of a cooperation of. That there must be a human influence include scientists, inter alia, the following analysis: Adding to the anthropogenic emissions of greenhouse gases from the climate models out, then shows up in the past 100 years except for some fluctuations in the long term hardly a change

slowing the warming

year blows humanity more CO2 into the air, increasing the amount of greenhouse gases in the atmosphere, which should accordingly continue to drive global temperatures up – or not? In fact, the average global temperatures have stabilized at a high level since the record warmth of 1998, there was no significant increase more. “But that is in the context of short-term fluctuations that overlay the long-term warming trend has always been,” said Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. Climate Trends longer periods from 30 years are crucial. The IPCC also emphasized that it was not likely that climate change is taking a break.

Why the fever curve of the earth has stagnated since the turn of the millennium is unclear. A thesis: It could be related to the oceans. Because the oceans are the largest heat storage. If vertical ocean currents provide such in recent years for a colder water surface, the oceans could absorb more heat. As a result, the air would heat up less near the ground. “The greenhouse effect has not diminished, there is only more heat in the deeper ocean and a little less close to the surface,” Rahmstorf said.


clouds

The climate impact of clouds seems mainly to depend on their structure and the height at which they float. To shield the flat fleecy clouds of the sun from the earth, thus they contribute to the cooling of the lower atmosphere. Cirrus clouds on the other hand, the form at altitudes above 6000 meters, allow visible sunlight almost unhindered through but block the reflected heat radiation from the Earth and thus help to retain heat in the lower atmosphere.

Which effect will predominate in the future? The IPCC considers it “likely” that clouds the future will increase the greenhouse effect sooner if global warming continues – but clouds remain a major uncertainty in climate predictions

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UN climate chief Christiana Figueres sees the results as a “wake up call” for the international community. “The report shows that there is more clarity about a human-generated climate change than ever before,” Figueres said. Past efforts to limit global warming was not enough. It pointed to the two-degree target, and that the states have agreed to provide this target in the light of scientific evidence to the climate summit in Paris in 2015 to the test. There are also the new global climate agreement will be adopted.

researchers cautioned to hurry. “There is a great need for political action to finally agree on the climate conferences,” said Latif of Mojib-GEOMAR Helmholtz Centre for Ocean Research Kiel. Stefan Rahmstorf said: “We actually have even less time than we thought.”

The two-degree target can only be achieved with the right course of action, said Federal Environment Minister Peter Altmaier (CDU) in Berlin. While the federal government was confirmed in its fight against climate change, environmental groups presented the previous black-yellow coalition from a bad witness. The CDU Business warned against competitive disadvantages for German or European unilateralism.

“Climate change is real, and it happens at an alarming rate,” warned the big NGOs WWF, Greenpeace, the International Trade Union Confederation, Oxfam, Friends of the Earth, ActionAid and Christian Aid. In a joint statement, the organizations urged governments to more stringent climate protection measures.

(AP, AFP, epd, mha)

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