Klimawandel vergrößert globale Süßwasserflächen: In den letzten 32 Jahren sind Wassergebiete von 170 mal dem Bodensee dazugekommen

Vor kurzem berichteten wir an dieser Stelle, dass die bekannte Klimawissenschaftlerin Judith Curry an ihrer Uni vorzeitig das Handtuch warf. Sie hatte genug von der klimaalarmistischen Beeinflussung. Ähnlich erging es nun auch dem Wissenschaftler Roger Pielke, Jr. an der University of Colorado, Boulder. Er setzte sich jahrelang für eine nüchterne Sichtweise bei Extremwetter und Versicherungsschäden ein. Nun kam auch sein Ende. Üppig finanzierte Aktivistengruppen brachten letztendlich auch ihn zu Fall, wie The Gazette berichtete. Pielke hat seine Klimaforschungsarbeiten jetzt eingestellt und ist nun Direktor des Zentrums für Sportmanagement seiner Uni. Wer fällt als nächstes?

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Im Dezember 2016 erschien in Nature eine Studie von Pekel et al., die weltweite Veränderungen im Oberflächenwasser während der letzten 32 Jahre anhand von Satellitenbildern kartiert hat. Das Ergebnis: In einigen Gegenden gibt es jetzt weniger Wasser, in anderen mehr. Abstract:

High-resolution mapping of global surface water and its long-term changes
The location and persistence of surface water (inland and coastal) is both affected by climate and human activity1 and affects climate2, 3, biological diversity4 and human wellbeing5, 6. Global data sets documenting surface water location and seasonality have been produced from inventories and national descriptions7, statistical extrapolation of regional data8 and satellite imagery9, 10, 11, 12, but measuring long-term changes at high resolution remains a challenge. Here, using three million Landsat satellite images13, we quantify changes in global surface water over the past 32 years at 30-metre resolution. We record the months and years when water was present, where occurrence changed and what form changes took in terms of seasonality and persistence. Between 1984 and 2015 permanent surface water has disappeared from an area of almost 90,000 square kilometres, roughly equivalent to that of Lake Superior, though new permanent bodies of surface water covering 184,000 square kilometres have formed elsewhere. All continental regions show a net increase in permanent water, except Oceania, which has a fractional (one per cent) net loss. Much of the increase is from reservoir filling, although climate change14 is also implicated. Loss is more geographically concentrated than gain. Over 70 per cent of global net permanent water loss occurred in the Middle East and Central Asia, linked to drought and human actions including river diversion or damming and unregulated withdrawal15, 16. Losses in Australia17 and the USA18 linked to long-term droughts are also evident. This globally consistent, validated data set shows that impacts of climate change and climate oscillations on surface water occurrence can be measured and that evidence can be gathered to show how surface water is altered by human activities. We anticipate that this freely available data will improve the modelling of surface forcing, provide evidence of state and change in wetland ecotones (the transition areas between biomes), and inform water-management decision-making.

Das Oberflächenwasser hat also kräftig zugenommen. Heute gibt es zusätzliche Wasserflächen in der Größe von 170 mal dem Bodensee, was enorm ist. Die zoomfähige Online-Karte gibt es hier. Aktivieren Sie “Water Occurrence Change Intensity” und wählen am besten einen weißen Hintergrund. Die Europäische Kommission gab am 6. Dezember 2016 eine Pressemitteilung zur Studie heraus:

Mapping long-term global surface water occurrence

In an article published in Nature on 7 December 2016, JRC scientists describe how, in collaboration with Google, they have quantified changes in global surface waters and created interactive maps which highlight the changes in the Earth’s surface water over the past 32 years.

Based on over three million satellite scenes (1 823 Terabytes of data) collected between 1984 and 2015, the Global Surface Water Explorer was produced using 10 000 computers running in parallel. The individual images were transformed into a set of global maps with a 30-metre resolution, which enable users to scroll back in time to measure the changes in the location and persistence of surface water globally, by region, or for a specific area. The maps are available for all users, free of charge. Where and when water is found on the planet’s surface is hugely important as it influences the climate system, the movement of species, sustainable development and social, institutional and economic security. While surface water is only a tiny fraction of the Earth’s water resources, it is the most accessible part, and provides wide-ranging ecosystem services.

This long-term history of the water-surface of the planet shows that total global surface water has increased over the past three decades, with over 180 000 km2 of new permanent water bodies forming in some parts of the planet and almost 90 000 km2 of permanent surface water disappearing from other areas. Much of the increase is linked to reservoirs and climate change (e.g. accelerated snow-and-glacier melt in Tibet), and the net loss (more than 70% of which occurred in Kazakhstan, Uzbekistan, Iran, Afghanistan and Iraq) is linked to drought and human activities such as river diversion, damming and unregulated use. The data show that the impacts of climate on where and when surface water occurs can be measured, and that the presence of surface water can be substantially altered by human activities. It will help to improve modelling scenarios, show where changes are occurring, and inform water-management decision-making. Combining this with other datasets, such as satellite altimetry measurements, could lead to estimates of surface water volumes, river discharge and sea-level rise, that will have additional benefits in helping to understand the impacts of climate change.

Of immediate use in climate science, water resource reporting and monitoring and commitments to multilateral environmental agreements, the authors expect that it will also find many other uses, such as in risk, resilience and recovery linked to water movement, infrastructural planning and yet others that are still to be imagined. Use of radar and optical satellite imagery from Sentinel-1 and Sentinel-2 of the EU Copernicus Programme will greatly help to improve the detail and accuracy of the information in the Explorer in the future.

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Gute Nachrichten am 4. November 2016 in den Geophysical Research Letters. Rebecca Thomas und Kollegen berichteten in einem Artikel über ein Ergrünen in den hohen nördlichen Breiten während der letzten Jahrzehnte, was die Forscher durch die Klimaerwärmung erklären. Zudem habe sich der saisonale CO2-Zyklus verstärkt, ein Effekt des gesteigerten CO2-Gehalts der Atmosphäre. Hier der Abstract:

Increased light-use efficiency in northern terrestrial ecosystems indicated by CO2 and greening observations
Observations show an increasing amplitude in the seasonal cycle of CO2 (ASC) north of 45°N of 56 ± 9.8% over the last 50 years and an increase in vegetation greenness of 7.5–15% in high northern latitudes since the 1980s. However, the causes of these changes remain uncertain. Historical simulations from terrestrial biosphere models in the Multiscale Synthesis and Terrestrial Model Intercomparison Project are compared to the ASC and greenness observations, using the TM3 atmospheric transport model to translate surface fluxes into CO2 concentrations. We find that the modeled change in ASC is too small but the mean greening trend is generally captured. Modeled increases in greenness are primarily driven by warming, whereas ASC changes are primarily driven by increasing CO2. We suggest that increases in ecosystem-scale light use efficiency (LUE) have contributed to the observed ASC increase but are underestimated by current models. We highlight potential mechanisms that could increase modeled LUE.

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Willis Eschenbach ging der Spur von angeblichen Klimaflüchtlingen an der US-amerikanischen Pazifikküste nach und stieß dabei auf seltsame Ungereimtheiten. Nachzulesen auf WUWT.

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Dilbert-Comiczeichner Scott Adams hat sich im Dezember 2016 in seinem Blog zum Klimawandel geäußert. Zunächst stellt er fest, dass er selbstverständlich den Konsensus der Klimawissenschaftler akzeptiert, denn alles andere würde seiner Karriere schaden, sagt er verschmitzt. Im Laufe seines Artikels führt er dann aber aus, dass sich die Mehrheit auch einmal irren kann. Auszug:

It seems to me that a majority of experts could be wrong whenever you have a pattern that looks like this:

1. A theory has been “adjusted” in the past to maintain the conclusion even though the data has changed. For example, “Global warming” evolved to “climate change” because the models didn’t show universal warming.

2. Prediction models are complicated. When things are complicated you have more room for error. Climate science models are complicated.

3. The models require human judgement to decide how variables should be treated. This allows humans to “tune” the output to a desired end. This is the case with climate science models.

4. There is a severe social or economic penalty for having the “wrong” opinion in the field. As I already said, I agree with the consensus of climate scientists because saying otherwise in public would be social and career suicide for me even as a cartoonist. Imagine how much worse the pressure would be if science was my career. 

5. There are so many variables that can be measured – and so many that can be ignored – that you can produce any result you want by choosing what to measure and what to ignore. Our measurement sensors do not cover all locations on earth, from the upper atmosphere to the bottom of the ocean, so we have the option to use the measurements that fit our predictions while discounting the rest.

6. The argument from the other side looks disturbingly credible.

Ganzen Beitrag in Scott Adams Blog lesen.