Das Team des Dual Fluid Reaktors gab vor kurzem eine Pressemitteilung heraus:
Wir freuen uns sehr, eine weitere spannende Kooperation mit einem exzellenten Partner bekanntzugeben: Dual Fluid hat mit dem kanadischen Teilchenbeschleunigerzentrum TRIUMF vereinbart, auf dem Feld der Materialforschung zusammenarbeiten. Damit haben wir eines der kompetentesten Forschungsinstitute für subatomare Physik an Bord geholt.
Material ist die Basis
Die Materialien unseres Reaktors müssen hohen Temperaturen, Strahlung sowie mechanischer Belastung über einen langen Zeitraum standhalten. Gemeinsam mit TRIUMF werden wir die vielversprechendsten Materialien eingehend untersuchen. Dafür stehen die weltweit führenden Protonen-bestrahlungsanlagen von TRIUMF bereit sowie einzigartige Werkzeuge, um Materie auf mikroskopischer Ebene zu analysieren. „Die Zusammenarbeit mit TRIUMF ist äußerst wichtig für uns, weil die Identifikation des besten Materials entscheidend für die weitere Entwicklung ist. Angesichts der Expertise von TRIUMF können wir uns keinen besseren Partner vorstellen“, so Ahmed Hussein, Chief Research Officer von Dual Fluid.
Unterdessen gehen die Sicherheits- und Stabilitätsanalysen für unseren ersten Leistungsreaktor voran. Unser internationales Forscherteam arbeitet hervorragend und gibt uns wichtige Impulse, von denen wir in vieler Hinsicht profitieren.
Dual Fluid in den Medien
Deutschland hält eisern am Atomausstieg fest und für die meisten Medien bleibt neue Kernkraft ein Nischenthema. Doch es gibt Ausnahmen: Die Schweizer Weltwoche gab Götz Ruprecht in einem Sonderheft zwei volle Seiten zur Vorstellung unserer Technologie. Bei der Achse des Guten erschien ein Gastbeitrag unseres Directors Titus Gebel. Auch bei YouTube und bei TikTok erschienen sehr interessante Videos, die mehrere hunderttausend Zuschauer fanden – das zeigt uns, dass das Interesse an neuer Kernkraft jenseits der etablierten Medien groß ist. Ein weiterer Grund zur Zuversicht!
Viel Spaß beim Schauen und Lesen und herzliche Grüße
Ihr Dual Fluid Team
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Successive, extreme cold events in the Northern Hemisphere this winter may be linked
Climate change is altering weather patterns, making it increasingly difficult to accurately predict extreme cold weather events in the short term.
A group of leading meteorologists recently determined that an important physical factor, the meridional potential vorticity gradient (PVy), was abnormally weak during the extreme cold weather events experienced simultaneously in East Asia and North America in November and December 2022. The team predicts that more accurate PVy modeling may improve forecasting of extreme cold weather events and future climate conditions.
The research team analyzed the atmospheric circulation that occurred during the frequent bouts of extreme cold experienced in the middle latitudes of the Northern Hemisphere in both East Asia and North America between November and December of 2022. The team found that, in both East Asia and North America, large, stationary blocking weather patterns prevented other weather systems from moving through, perpetuating the cold weather in both locations.
Further analysis revealed that the PVy, a meridional gradient of potential vorticity in the atmosphere, was unusually weak during this time, and likely contributed to the prolonged cold weather and associated snow events observed in these regions.
The research team reported their results in Advances in Atmospheric Science on February 9.
„In our previous study, we found that frequent cold waves were more likely to occur in mid-latitude Asia in the upcoming 2022-2023 winter season under the background of a warm Arctic and a cold tropical Pacific. In our current study, we wanted to know what actually caused these cold surges and if the cold events in North America and East Asia were related,“ said Yao Yao, lead author of the research study and associate professor at the Chinese Academy of Sciences (CAS) Key Laboratory of Regional Climate-Environment for Temperate East Asia in the CAS Institute of Atmospheric Physics (IAP).
The research team’s November 2022 prediction proved correct, as extreme cold events have been frequent in the middle latitudes in Asia for at least the first half of the 2022-2023 winter season. Further analysis in the current study additionally revealed a weak connection between the extreme cold event experienced in East Asia around November 26, 2022 and the cooling with tornadic outbreaks and „bomb cyclone“ observed in North America in mid- and late December 2022, respectively.
The unusually weak potential vorticity gradient of the middle-latitude Northern Hemisphere atmosphere during this timeframe facilitated the development of stationary blocking weather patterns in both the Ural Mountains and Alaska, causing the frequent extreme cold weather and snowstorm events in East Asia and North America, respectively.
Abnormally weak atmospheric meridional potential vorticity gradients not only create favorable conditions for blocking weather patterns, but also decrease their predictability. „As a result, the difficulty of predicting cold extremes increases,“ said Dehai Luo, co-author of the research paper and professor at the CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia in the CAS IAP. Existing models are simply less effective at accurately predicting the movement of blocking weather patterns when potential vorticity gradients are so low.
„Low Arctic sea ice and La Niña favor the reduction of mid-latitude potential vorticity gradients, but there are many other factors affecting this gradient. The next step is to identify these factors and try to establish a relatively sound statistical model, which is important for short-term weather and climate prediction,“ Yao said.
Once these factors are determined through future study, blocking weather pattern predictability will increase. „Such a study will likely improve the prediction of winter cold extremes,“ Luo said. Ideally, improved forecasting will decrease the often devastating economic losses and casualties that can occur with unexpected cold snaps.
Papers:
Yao Yao et al, Extreme Cold Events in North America and Eurasia in November−December 2022: A Potential Vorticity Gradient Perspective, Advances in Atmospheric Sciences (2023). DOI: 10.1007/s00376-023-2384-3. link.springer.com/article/10.1 … 07/s00376-023-2384-3
Fei Zheng et al, Can Eurasia Experience a Cold Winter under a Third-Year La Niña in 2022/23?, Advances in Atmospheric Sciences (2022). DOI: 10.1007/s00376-022-2331-8
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Das Wissenschafts-Startup re:look Climate hat sich Darstellungen mit Temperaturstreifen angeschaut. Hier Teil 2 der Analyse:
Über Temperaturstreifen – Teil 2: Der abgebildete Datenzeitraum
Philipp Lengsfeld und Hans-Peter Stricker, re:look climate gGmbH
Der zweite zentrale Punkt bei der Nutzung von Klimastreifen für die aktuelle Klimadiskussion ist die Frage, welche Daten überhaupt gezeigt werden. In der populären Variante – und dies sehen Sie auch auf der Webseite „#showyourstripes“ des Originators Dr. Ed Hawkins – werden praktisch ausschließlich Temperaturkurven der Neuzeit präsentiert. Dies wird im Bereich FAQs („häufig gestellte Fragen“) so erklärt: Die Intention ist die Darstellung von Temperaturmessungen der letzten 100+ Jahre. Einige Datensätze gehen bis 1850, aber meistens werden Daten ab 1900 gezeigt.
Es gibt aber keinen wissenschaftlichen oder inhaltlichen Grund, die Darstellung der Temperaturverläufe auf die letzte 100-180 Jahre zu beschränken. Denn es gibt Temperaturdaten, die deutlich weiter in die Vergangenheit gehen und aus klimawissenschaftlicher Sicht sind solche Daten natürlich von hohem Interesse. Denn durch Vergleich mit Daten aus der Vergangenheit kann man sich z.B. der wichtigen Frage nähern, welche Auffälligkeiten die Temperaturverläufe der letzten 150 Jahre im Vergleich zu Daten aus der Vergangenheit zeigen, z.B. steilere, also schnellere Änderungen (Anstieg oder Abfall) oder vorher nie erreichte Werte.
Es gibt hier nur eine inhaltliche Hürde, die aber aus unserer Sicht kein prinzipielles Problem darstellt: Die ältere Datensätze sind nicht von zuverlässigen Temperaturmessstationen, sondern beziehen sich in der Regel auf sogenannte Temperaturrekonstruktionen. Zusätzlich enden Teile dieser Rekonstruktionen einige Jahre oder Jahrzehnte vor der heutigen Zeit.
Aber auch das ist kein prinzipielles Problem: In den Klimastreifen kann man durchaus zwei Datensätze darstellen, es ist aber in der vereinfachten Darstellung nicht möglich, Überlappungen zu zeigen (dies ist in regulären Darstellungen völlig problemlos möglich). Man müsste an den Klimastreifen deshalb den Punkt markieren, an dem der eine Datensatz aufhört und der andere anfängt.
Im Folgenden sehen Sie Datensätze, die deutlich über den von Ed Hawkins favorisierten Bereich hinausgehen. Zunächst eine Temperaturrekonstruktion der Arbeitsgruppe um Ulf Büntgen mit der Temperatur der nördlichen Hemisphäre der letzten 2000 Jahre.
Weiterlesen bei re:look Climate
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Kevin Trenberth auf The Conversation:
New Zealand wants to tax cow burps—here’s why that’s not the best climate solution
New Zealand, where agriculture is one of the largest contributors to climate change, is proposing a tax on cow burps. The reason seems simple enough: Cows release methane, a potent greenhouse gas, and New Zealand has a goal of reaching net-zero emissions by midcentury. Right now, the country’s effects on climate change come roughly equally from carbon dioxide and methane.
Worldwide, 150 governments have committed to cut methane emissions, both from agriculture and by cracking down on the largest source – fugitive leaks from natural gas pipelines and other fossil fuel infrastructure.
But is methane from cows really as bad for the climate as methane from fossil fuels? And given its shorter lifetime in the atmosphere, is methane as bad as carbon dioxide?
The answers involve renewable resources and the so-called circular economy. Understanding the effectiveness of different strategies is important as countries plan their routes to net-zero emissions, which is necessary for the world to stop further climate change.
Moreover, emissions must not just reach net-zero, they must stay there.
Targeting methane
I am a climate scientist who has spent decades studying global warming. Evidence has clearly established that human activities are causing climate change. Humans have released so much carbon dioxide into the atmosphere since beginning to burn fossil fuels in the 1800s that the accumulated gases are now trapping significantly more heat than is released to space. The result is global warming.
Some carbon dioxide stays in the atmosphere for hundreds to thousands of years. But methane, the second-most important greenhouse gas, lingers in the atmosphere for only about a decade before being oxidized to form carbon dioxide.
Although methane doesn’t last as long, it is many times more potent than carbon dioxide at warming the climate. That’s why it’s a target for policymakers.
However, its effects can be misjudged. A rough equivalence of the heating from methane to that of carbon dioxide is often used to estimate its effects on the climate, but the number varies by the time frame.
The global warming potential typically used for methane is 28 times that of carbon dioxide for a 100-year period. But a spike in methane has no effect after about 30 years because the methane is well gone by then. So, methane’s effects on temperature are greatly overstated over centuries, while considerably understated over the first 20 years. Indeed, scientists have argued that short-lived climate pollutants such as methane should be split out from long-lived ones such as carbon dioxide when making policy.
Moreover, biogenic sources of carbon, such as from trees or cattle, are renewable, while fossil fuel sources are not.
Weiterlesen auf The Conversation
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Die Deutsche Rohstoffagentur (DERA) hat am 6. April 2023 einen Bericht zu Rohstoff-Trends veröffentlicht. Das pdf gibt es hier.
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What caused the record-low Antarctic sea ice in austral summer 2022?
Antarctic sea ice is an important component of the climate system, and may act as an early indicator of climate change. Under global warming, significant changes in Antarctic sea ice have been observed. Specifically, it experienced a slow increase during 1979–2014, but a rapid decline thereafter.
Despite a modest recovery after the record minimum in 2017, the sea ice area during austral summer 2022 (December 2021 to February 2022) again hit a new record minimum, at 3.07 million km2, which is approximately a 25% reduction compared with its long-term mean during 1981–2010. The largest decline occurred in two regions: the central-eastern Ross Sea to western Amundsen Sea, and the eastern Bellingshausen Sea to the northern Weddell Sea.
This latest record low occurred just five years after the preceding record low in summer 2017, which is surprising and has raised concern about climate change in the Antarctic. In a paper recently published in Atmospheric and Oceanic Science Letters, Prof. Shuanglin Li from the Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China, and Dr. Chao Zhang from the China University of Geosciences, Wuhan, China, attempt to uncover the underlying mechanisms of this record-low sea ice area.
„We found that the combination of stronger positive sea surface temperature anomalies in the Maritime Continent during July–September 2021 and the preceding near-strongest positive-phase Southern Annular Mode during August–October 2021 induced a deepened and southwestward-shifted Amundsen Sea Low, causing sea ice retreat via horizontal wind anomalies,“ explains Prof. Li.
The former persisted into summer and favored the development of La Niña, which triggered an atmospheric wave train emanating from eastern Australia and propagating southeastward, deepening the Amundsen Sea Low remotely. The latter remained strongest or close to strongest due to the stratospheric cooling effect of unprecedented ozone reduction, which induced a deepened and southwestward-shifted Amundsen Sea Low.
„The unprecedented ozone reduction also played a role through the induced surface warming in the West Antarctic by increasing downward shortwave radiation. Additionally, positive feedback between sea surface temperatures, net shortwave radiation, and cloudiness, along with the Ekman heat transport, amplified the surfacing warming,“ adds Prof. Li.
Chao Zhang et al, Causes of the record-low Antarctic sea-ice in austral summer 2022, Atmospheric and Oceanic Science Letters (2023). DOI: 10.1016/j.aosl.2023.100353
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Wir wünschen alles Lesern ein frohes Osterfest!
Kleiner Programm-Hinweis: Heute endet die Winterpause der Klimaschau. Um 13:00 Uhr erscheint heute (9.4.2023) Ausgabe 143. Thema: Der geheimnisvolle nordatlantische Zyklus. Nicht verpassen! Wo: EIKE-Kanal auf Youtube.