Hamburg meteorologists have a prognosis for the climate in Germany at the end of the 21. Town hundred
Climate change is expensive, the Federal Environment Agency (UBA) is safe. Not only in the poor countries who see in the tropics or as small island states to see the unbillary change in a special mabe. Also in Central Europe is expected with drastic changes in precipitation patterns, average temperatures and flood hazards, the concentration of atmospheric greenhouse gases should continue to increase. For the first time, Hamburg meteorologists have a detailed forecast for the time towards the end of the 21. Century dared to the 25. April was presented on a joint workshop by UBA and the Hamburg Max Planck Institute for Meteorology.
There is no shortage of warnings before climate change. In 2003, for example, in a joint explanation of the meteorological societies in Switzerland, Austria and Germany, it bothered:
Although the causes of the observing climate change are complicated and the role of natural climate change is by no means sufficiently clarified, the global emphasis on the last 100 – 150 years is highly probably back on human activities, especially on the static outstool from carbon dioxide (CO2) and other climate-effective trace gases related to the use of fossil energy carrier (coal, oil and natural gas, including traffic) and forest. If the ie of these gases continue to rise very much as before, a temperature increase (ground close) is omitted from 1.4 to 5.8 ° C for the coming 100 years in the global agent.
Meanwhile we know it a bit more specifically. With a regional climate model was calculated in Hamburg that it becomes warm, especially in the south and sudeness in Germany, especially in the Alps. There, the winter boots will increase significantly, but there will be less than snow due to the high temperatures. Since rain resorts immediately, this means an increased flood risk. In the summer months, however, the precipitate will become less, which will suffer considerably in many areas of agriculture and forestry. Accordingly, you can see in the UBA black, which is concerned with the high level of climate damage:
Over the past ten years alone, the damage amounted to the coarse flood of Isar, Lech, Iller and Inn (1999 and 2005), the Elbe and the Cloud (2002), at or (1997) and Rhine, Mosel, Saar and Maas (1993 and 1995) to around 13 billion euros. Heat and Durre caused about one billion euros damage. Due to the storm Jeanette, Daria, Vivian, Wiebke, Lothar and Martin, costs of a total of about 2.5 billion euros4. As a result of these extreme events in Germany were estimated more than 7.000 Death trap to complain. The weather and cinnamoned damage costs were allowed to increase exponentially and could amount to about 27 billion euros in the middle of the century by the middle of the century.
Art Climate Changes in Germany
The 7.000 dead were quite victims of the Hitzwelle in 2003. According to the World Meteorology Organization (WMO) there was about 21.000 Tote in Western Europe. The UBA indicates that the heat-related health problems met Germany relatively unprepared. "It lacked medical knowledge, declaration and precautionary acceptances as well as warning systems."
A basis for clearing and also warning systems could create artificial models like the Hamburg Remo. The unusual of the calculations of the Hamburg meteorologists, which the UBA damage forecasts are defrosted, is their little room. For customary are the computer models with which meteorologists and other climate scientists take a look into the future of our climate gross gross. This is due to the tremendous FULLE on arithmetic operations that are necessary to map the complex processes. Pictorially speaking, a grid is placed over the globe, at whose nodes for each time step the movement of the atmosphere are calculated. Looking roomy processes such as cloud formation, downstream and pulse, energy and water vapor exchange with the water, land and ice-headers must be parameterized. Accordingly, the forecasts which can be calculated with the models can, at best, mean values for coarse regions.
Three different scenarios for the development of the emissions of the CO2, the most important greenhouse gas, (the other greenhouse gases are customary in CO2-aaquivalent) and the development of sulfur dioxide emissions (SO2). SO2 forms in the atmosphere small floating particles (aerosols), which are obvious to the causes of the acid rain, but at the same time have a cooling effect on the climate. Source: Climate Projections for the 21. century
The Hamburg climate researchers use two coupled models for their global forecasts: On the one hand, the ECHAM5 that simulates atmosphere and land tops, and on the other hand the ocean model MPI-OM. The horizontal resolution of the atmosphere model amounts to 1.875 degrees, which corresponds to the equator a lattice spacing of about 200 kilometers. The ocean model expects with abordments of 1.5 degrees accordingly about 160 kilometers at the equator.
With such models you can investigate how sensitively the global climate on changes in the concentration of greenhouse gases. For different scenarios of the increase of CO2 can be calculated a rough regional temperature distribution and also covering with snow and ice. The Hamburgers have compared several scenarios before a good year, which will be found in the next report of the United Nations Committee for Climate Change (IPCC), which appears in the next year.
The most favorable variant provides for an increase in greenhouse gas emissions by 2040 by 50 percent and a subsequent ridge to the half of today’s level until the year 2100. The latter would probably equivalent to a stabilization of the concentration in the atmosphere, because at least under present conditions take oceans and biosphere in about half of the emissions to only 50 percent of what comes out of internal combustion engines and Entwaldungsprozessen into the atmosphere, stays there to also langerfristig contribute to the greenhouse effect. Even in this, considering the political realities gegenwartigen optimistic scenario, the temperature at the end of 21. Century the global average by 2.5 degree rise (reference period are the 1961 and 1990). For the ungunstigeren variants Hamburg say an increase by 4.1 degrees forward. In all cases, the Arctic is particularly strong to warm and the local sea ice in summer depending on the scenario disappear almost completely or.
The Polarmeer. Above today’s condition, including forecasts for the end of the century. The (extensive) disappearance of the year-round ice is significantly accelerate the thawing of the permafrost floor. This releases rough amounts of CO2 and, above all, the still more efficient greenhouse gas methane (CH4), a positive ruck coupling, which is not considered in the climate models so far. Source: Climate Projections for the 21. century
What you can not do this coarse models is more accurate predictions for so small areas such as Switzerland or Germany. Therefore, in Hamburg, in collaboration with other a so-called regional model (REMO) has been developed, which can be taken into a closer look with a magnifying glass partial areas. In this Remo, the lattice chart can be reduced to 50 or even 10 kilometers as needed. At the randoms, the values calculated by the above-described basic model are entered, including, among other things, the sea surface temper cell. With this refined model, the Hamburg Remo Group calculated that in Germany BSI at the end of the century, the middle temperatures will increase by 2.5 to 3.5 degrees Celsius by 2.5 to 3.5 degrees. However, the emphasis varies geographically and seasonally. The strongest is the winter in the south, namely up to four degrees. At the same time, summer downlinks will decrease throughout the country. However, this racy will be particularly pronounced in the Suden and South East (by 30 percent) and in the northeast (25 percent). Together with the emphasis, the already existed for decades from the acid rain-degraded Walder under enormous stress. The climatic zones are shifted northwarts and many plant species will not be able to hike afterwards quickly enough.
Changing the winter temperatures. Source: UBA
The Remo has been tested for various real weather events of the past, which could be reproduced quite well. Such tests are necessary to get an impression of how well the computer models reproduce the real relays. For this purpose you take the observation data and then let the model with these one time period the weather or. Determine the climate of a specific region. This has been made at Remo, for example, with the Odshochwasser of July 1997 and came to a drain rate of or – that is in this case for the hydrologists of the critical value – on an amount that was only about ten percent under the actually arrived. This is for a climate model, which should actually calculate only mean values over a longest period of time, a considerable accuracy.
Decline of summer boots. Source: UBA
The conclusions that the UBA draws from the results of the Hamburg Remo Group are not necessarily new, but for a federal agency in its consequence, after all, remarkable: the concentration of atmospheric CO2 must be at a level of less than 400 million parties (ppm, parts per per Million) are stabilized (currently the middle CO2 content of the atmosphere 381 ppm, 1880, when the industrial revolution was still in its infancy, it was 280 ppm).
In order to achieve stabilization, the greenhouse gas emissions must be reduced to the half of 1990 levels by the middle of the century worldwide. The industrialized countries, according to the UBA, are in a special responsibility as they have to leave the developing policies. Their emissions had to be reduced by 80 percent in the next 44 years. For Germany, a reduction was 40 percent to 2020 and 80 percent to 2050 "technically possible and economically trusted".
Each zogern in climate protection becomes expensive, as the loss costs were allowed to grow progressively for climatefoly damage: the global cost of demanding climate protection is a average of one percent of global economic performance – and thus far below the economic consequences of unbraked climate change, whose damage is up to ten percent of worldwide Economic performance could make up. Germany has the necessary knowledge and can be quickly encountered to climate change. A fast and significant increase in energy efficiency in power plants and energy use as well as the strong use of renewable energies are crucial for this purpose.
The UBA in a collapse of the results of the mentioned workshop
Remains to note that even the goal of stabilizing the CO2 concentrations under 400 ppm, that is more or less on the present level of 381 ppm, another emphasis will be dragging. In the last 100 years, the overall of the globe and the whole year averaged temperature of the ground-level atmosphere increased by 0.6 degrees. In Germany, the increase was 0.9 degrees.
Even if you could freeze the greenhouse gas concentration from today on tomorrow, the temperature rise was still going on a few tenths of degree and thus the shifting of the climates and changes in precipitation distribution and probably also the increase in extreme events. The reason for this is the constitution of some components of the climate system. Until the entire cover layer of the oceans has adapted to the new boundary conditions, it takes decades. Likewise, the glaciers of the high mountains will need several decades until they have found a new balance. Particularly bearing are the deep water of the oceans and the glaciers of the Antarctic, which are more likely to expect in millennia.
