球温暖化による熱波、干魃、台風、洪水などの異常気象が増加。
Un clima cada vez más extremo
Los científicos alertan de que sequías, inundaciones y otros fenómenos radicales se acentúan 13 de los 14 años más cálidos se han producido en lo que va de siglo
El cultivo del olivo en España se beneficiará del cambio climático
Elena G. Sevillano Madrid 24 MAR 2014 - 22:11 CET
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An increasingly extreme weather
Scientists warn that droughts, floods and other radical phenomena are accentuated 13 of the 14 warmest years have occurred so far this century
Olive cultivation in Spain will benefit from climate change
Elena G. Sevillano Madrid 24 MAR 2014 - 22:11 CET
Heat waves , droughts , cyclones , floods ... The year 2013 has been a good example of how extreme weather events impacting entire communities and regions. The Haiyan typhoon devastated areas of central Philippines , Oklahoma (USA ) suffered the largest tornado ever observed , unprecedented snowfall will hit Israel , Jordan and Syria. The annual statement of the World Meteorological Organization (WMO ) on the state of global climate , filed yesterday in Geneva, warns that extreme weather events are accentuated and insists : the influence of human activity on climate explains some of the changes that are being observed .
One expert says: " We see many episodes occur as anticipated "
The global warming trend is still shaping itself long-term statistics . The 2013 has been, along with 2007 the warmest year since records began . But also, as highlighted by the WMO report , 13 of the 14 warmest years have occurred in the XXI century. Each of the last three decades has been warmer than the previous one ( the record is 2001-2010). The average temperature in the soil and on the surface of the oceans last year was 14.5 degrees Celsius, ie average degree increased from the average of the sixties , seventies and eighties. Data records that result in : Australia recorded the warmest year on record , Argentina , the second .
Can all or part of these phenomena attributed to global warming ? Jessica Blunden , a scientist at the National Oceanic and Atmospheric Administration ( NOAA) and one of the authors of the study, notes that " there has always been , and always will be , extreme weather and climate events and natural variations due to factors such as El Niño or La Niña "but remember that the Intergovernmental Panel on Climate Change (IPCC , its acronym in English ) in September said that warming is" unequivocal "and that" human influence is clear. "
More rain and the drought in Spain again
E.G.S.
The report of the WMO (World Meteorological Organization ) stands about Spain that rainfall during 2013 were 20 % higher than the historical average , but with " large geographical differences." While some coastal areas of the Atlantic showed an increase of 50% on the normal values of the Mediterranean regions were drier than average. The month of March was the wettest since no national records (1947 ) , the report added .
" More than how much it has rained , the abnormal has been how : all the west, a storm from the Atlantic arrivals after another ," explains Ana Casals , spokesman for the Spanish Meteorological Agency ( Aemet ) . "We had record number of days with storms at sea and red notice. However, in Valencia , drought has been high. Records of 151 years in the city, never in a little water winter was so registered , "he adds .
Temporary at sea have been one of the outstanding features of the year. The Aemet conducted a study to analyze the waves. He concluded that since 1957 he had not been another winter with both waves, but not because of the intensity or wave height , but the frequency of episodes . The Aemet decreed seven red alert level by strong waves when it will normally not exceed two or three.
The climatic peculiarities include the rest of Europe , as enumerated in the report of the WMO , the wettest summer in the UK since 1910 and the unusual - for - high temperatures in Sweden in February. Turkey, however, had 13% less rainfall than usual , generating drought.
"We see many cases where extreme events occur as scientists had projected based on climate change ," says Blunden by email. "For example, in different areas around the world have predicted more extreme heat waves , copious showers and more intense droughts , and now we are seeing that these phenomena occur . Unfortunately, it is not easy to analyze and attribute as happen or not climate change , "he adds . To explain, Blunden refers to a study that incorporates the WMO report about record temperatures in Australia in 2013.
The work , by scientists at the University of Melbourne ( Australia ) , nine climate models used to study whether changes in the probability of extreme temperatures were registered during the Australian summer were due to human influence. Showed that the 2013 record as warmest year " would have been virtually impossible without the heat-trapping gases of human origin , which shows that some extreme events is much more likely to occur due to climate change." In this case , says Blunden , "the study establishes a direct link between climate change and the unprecedented heat ."
Also Secretary General of WMO, Michel Jarraud , said yesterday during the presentation of the report , "many of the extreme weather events that occurred in 2013 were consistent with the expected consequences of climate change had caused by human activity " . Examples: " Precipitation stronger , more intense heat and a greater number of damage caused by storm surges and coastal flooding as a result of sea level rise ." The Typhoon Haiyan would be the best example of this , he added .
Manuel de Castro , a professor at the University of Castilla -La Mancha and one of the Spanish authors of the IPCC report says that there are some extreme events that relate to security with climate change , "especially when we talk about heat waves , since there is clear evidence that there is a growing trend, " he says. In other episodes, as torrential rains and tropical cyclones, " there is less evidence , but that does not mean they can not be attributed to global warming." "It's a plausible explanation but can not guarantee one hundred percent until we have more evidence ," he adds .
With such a scenario , weather forecasting systems are essential , says Blunden . "Especially for the growth of densely populated megacities , usually located in coastal areas vulnerable to cyclones, floods and floods ." He adds: " Thanks to the predictions , India was able to evacuate more than a million people by the tropical cyclone Phailin , and greatly reduced the loss of life ."
The olive growers will benefit
ALICIA RIVERA
The increase in the average temperature of the Earth by 1.8 degrees Celsius by mid-century , become more profitable cultivation of olive trees in the Mediterranean basin , especially in North Africa , where profits can increase by 41 % . The average increase of the crop in the area is 4.1% , but there will be winners and losers at the regional and local level.
In Spain , the overall trend is positive , towards greater profitability of this historic drought tolerant crop ( limited only by hard frosts and excessively high temperatures), although the impact will be negative in some areas of the center of the Iberian Peninsula . A group of scientists has examined the likely trend of olive groves in the conditions imposed by climate change in the Mediterranean , from which 97% of world production.
The research, published this week in the journal Proceedings of the National Academy of Sciences, takes into account the response of the plant (Olea europea ) heating conditions , such as olive fly (Bactrocera oleae ), its major pest , and the interaction between them , as again and have different tolerances to temperature. Ie in a region can not increase much harvest but if markedly reduced infection impairs the olive fly and reduces productivity Tree , profits may rise significantly. Do not forget that climate projection models indicate that the Mediterranean, due to the increased concentration of greenhouse gases in the atmosphere , undergo a remarkable rise in temperature , but the olive has limits within which can survive productivity or even win , while the fly that infects is conditioned by different margins .
Flowering olive advance throughout the Mediterranean Basin on the current average seasonality, becoming 18 days ago in areas of the Iberian Peninsula , North Africa and Greece.
The benefits of growing exploitation of the olive tree will increase in areas of Spain and Italy due to higher yields, which more than offset the levels of infection of the fly, the higher cost of its prevention and elimination as well as lower oil quality conclude Luigi Ponti (National Agency for New Technologies , Energy and Sustainable Economic development , Rome ) and colleagues . However, in some areas of the center of the Iberian Peninsula and northern Portugal benefits will decrease due to high levels of infection and its associated costs.
In North Africa , however , the benefits increase, although slightly reduced yields due to lower level of infection of the fly, cutting costs to cope and improved oil quality. In the Middle East , yields decrease.
The expected changes in productivity in each place are due mainly to the different effects of increased temperature on the fly and the olive tree. Thus, despite the overall average increase of crops in the Mediterranean basin of 4.1% , scientists anticipate a reduction in the level of infection of 8% and an increase of net profits from the exploitation of culture 9.6 % . Fly populations and decrease in high areas with cold winters , and in areas where summer temperatures rub or exceed the maximum tolerable by this species .
Ponti and colleagues warn that the trees of low profit probably be abandoned in many places , resulting in greater potential for fires irrigation, soil degradation and loss of biodiversity.
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