Neues von der Grünen Sahara

Nun läuft bei allen deutschen KKW der Rückbau. Alex Reichmuth zeigt im Nebelspalter auf, wieso beim Abbruch von Kernanlagen geradezu schikanös strenge Auflagen gelten. Die Anti-Atom-Lobby hat es so gewollt.

Schikanös strenge Bedingungen beim Rückbau

Sieben Jahre. So lange dauerte es, bis der deutsche Stromkonzern Energie Baden-Würtemberg (EnBW) im vergangenen April endlich die Genehmigung für die Stilllegung und den Abbau des Kernkraftwerks Neckarwestheim 2 erhielt. Sieben Jahre sind mehr, als der Bau des AKW seinerzeit gedauert hat, denn dafür waren nur sechs Jahre nötig. Beantragt hat EnBW die Rückbaugenehmigung bereits 2016.

Neckarwestheim 2 ist eines der drei letzten deutschen Atomkraftwerke, die vor kurzem abgestellt wurden. Damit ist die Zeit des Atomstroms in Deutschland vorbei. Nun beginnt bei diesen Anlagen die Phase des Rückbaus, die voraussichtlich 15 Jahre dauern wird.

Weiterlesen im Nebelspalter.


BILD-TV auf Youtube:

Viertel nach Acht – 10. Mai 2023 | LIVE u.a. mit Dr. Fritz Vahrenholt und Antje Hermenau

Es ist der Talk, der Schlagzeilen macht! In der TV-Sendung „Viertel nach Acht“ diskutieren bei BILD fünf hochkarätige Gäste über tagesaktuelle Themen. Knallharte Meinungen, offene Gespräche und ehrliche Diskussionen – nur im BILD Live. Heute begrüßt Patricia Platiel folgende Gäste bei Viertel nach Acht: – Antje Hermenau / Politikerin (ehemals Bündnis 90/Die Grünen) – Prof. Dr. Fritz Vahrenholt / Ehemaliger Umweltsenator Hamburg (SPD) und Energieexperte  – Tobias Bauschke / FDP-Politiker (Berlin) – Heinrich Strößenreuther / Umweltaktivist, Unternehmensberater, Autor und Vorstand „KlimaUnion“   Diese Themen erwarten euch: – „Ampel-Politik treibt Wähler zur AfD“ – „Elektro ist die Zukunft“ – „Habeck zerstört das Land“ – „Wer zu uns will, muss arbeiten“


Yacoub et al. 2023, unter Beteiligung von Stefan Kröpelin:

The African Holocene Humid Period in the Tibesti mountains (central Sahara, Chad): Climate reconstruction inferred from fossil diatoms and their oxygen isotope composition

The climate of the African Holocene Humid Period (AHHP) is reconstructed in the Tibesti Volcanic Massif (TVM) in the central Sahara from well-preserved diatomaceous deposits in the two crater palaeolakes of Trou au Natron at Pic Toussidé and Era Kohor at Emi Koussi. The two records cover the period from ∼9500 to 4500 cal yr BP. Climate and palaeoenvironmental changes during this period were inferred from diatom assemblages, interpretation of variations in their oxygen isotope composition (δ18Odiatom), reconstruction of lake water conductivity from diatom-based transfer functions, and estimation of the lake water balance (Evaporation/Inflow ratio, E/I). Our findings provide evidence for two distinct lacustrine episodes. During the early to mid-Holocene transition, low δ18Odiatom values, high percentages of planktonic diatoms, low lake water conductivity and a positive water balance (E/I < 1) suggest wet conditions, which were likely related to the optimum of the AHHP. From the mid-to late Holocene transition, an aridification trend is revealed by increasing δ18Odiatom values, high percentages of benthic diatoms and a negative water budget (E/I > 1), occurring as early as 6500 cal yr BP and intensifying after 5300 cal yr BP. Moreover, our data show on average a decrease in precipitation amounts of ∼35% between the peak and the end of the AHHP in the Tibesti region. This timing of the AHHP in the mountainous Tibesti is consistent with the aridification of the central Sahara recorded at lowland sites, which has mainly been related to the southward retreat of the Intertropical Convergence Zone (ITCZ) and the associated African monsoonal rainfall belt, following the gradually declining summer insolation that led to the termination of the AHHP. Our results prove the existence of Holocene lakes in the TVM craters that developed contemporaneously with the lakes of the Chadian basin and the Libyan Sahara. On a broader scale, our data share similar hydroclimatic patterns with studies from the eastern and northern Sahara.


University of Leeds:

Deforestation in the tropics linked to a reduction in rainfall

Deforestation is resulting in reduced rainfall across large parts of the tropics, according to new research.

People living in tropical forest communities have often complained that the climate gets hotter and drier once trees are cleared but until now, scientists have not been able to identify a clear link between the loss of tree cover and a decline in rainfall.

A research team at the University of Leeds combined satellite data of deforestation and rainfall to show that the loss of tree cover in the tropics over the last 14 years was associated with reductions in rainfall.

They estimate that by the end of the century, if the rate of deforestation in the Congo was to continue, rainfall in the region could be reduced by between 8% and 12%, with major impacts on biodiversity and farming, and could threaten the viability of the Congo forests, which are among the world’s largest stores of carbon.

Callum Smith, a doctoral researcher in the School of Earth and Environment at Leeds and the lead author in the study, said the investigation provides “compelling evidence” to protect forests from uncontrolled clearing.

He added, “Tropical forests play a critical role in the hydrological cycle through helping to maintain local and regional rainfall patterns. The reduction in rainfall caused by tropical deforestation will impact people living nearby through increased water scarcity and depressed crop yields.

“Tropical forests themselves rely on moisture to survive and remaining areas of forest will be impacted by a drier climate.”

The research paper, “Tropical deforestation causes large reductions in observed precipitation,” is published today (Wed, March 1) in the journal Nature.

The researchers looked at the impact of forest loss in three areas of the tropics—the Amazon, Congo and Southeast Asia—which have all experienced rapid land-use changes. The study involved analysis of satellite observations from 2003 to 2017, to identify locations where forests had been cleared. Rainfall data in these areas, also measured by satellites, was compared to rainfall from nearby locations where forests had not been lost.

The study revealed that tropical forest loss caused reductions in rainfall throughout the year, including in the dry season when any further drying will have the biggest ramifications on plant and animal ecosystems. The greatest absolute decline in precipitation was seen in the wet season with up to a 0.6 mm a month reduction in rainfall for every percentage point loss of forest cover.

Writing in the paper, the researchers warn that climate change will lead to increased drought and that will be exacerbated by continued deforestation.

It is believed the loss of tree cover disrupts the process where moisture from leaves—through a mechanism called evapotranspiration—is returned to the atmosphere where it eventually forms rain clouds.

As well as impacting natural ecosystems, a reduction in rainfall would be detrimental to agriculture and hydropower plants. That would have a strong impact both on the healthy functioning of the forests and on local communities.

The research team say, on average, crop yields declined by 0.5% for every 1% reduction in rainfall.

Professor Dominick Spracklen, from the School of Earth and Environment at Leeds who supervised the project, said, “Local people living near deforested regions often report a hotter and drier climate after the forests are cleared. But until now this effect had not been seen in rainfall observations.

“The study shows the critical importance of tropical forests in sustaining rainfall. Although there have been efforts to halt deforestation, the loss of forest cover in the tropics has continued. There needs to be renewed efforts to stop forests being lost and to regenerate lost and degraded areas.”

The scientists warn that a decline in rainfall has a negative impact on biodiversity, increases the risk of forest fires and reduces carbon sequestration, where nature removes carbon from the atmosphere and stores it.

Callum Smith, Tropical deforestation causes large reductions in observed precipitation, Nature (2023). DOI: 10.1038/


World not adequately prepared for disasters, report says

Earthquakes, floods, storms—the world is not adequately prepared to face increasing disasters, said a report published Tuesday calling for a rethink on global risk management.

Weiteerlesen auf


Kat Kerlin, University of California Davis:

Study reveals shifting climate trends in the Western US dating back 11,000 years

People often say that Phoenix has always been dry; Seattle has always been wet; and San Francisco has always been foggy. But “always” is a strong word.

A study from the University of California, Davis, synthesizes climate trends across the Western U.S. during a relatively recent period of Earth’s history—the Holocene Era, which stretches from the present day to the past 11,000 years. This look at the really Old West shows that the hallmarks of California’s climate—the foggy coastlines that gave rise to towering redwoods, the ocean upwelling that spawned productive fisheries, the warm summers and mild winters—began around 4,000 years ago.

It also reveals a time when the Pacific Northwest was warm and dry and the Southwest was warm and wet.

An understudied era: The current one

Published in Climate of the Past, the study provides a baseline against which modern climate change in the region can be considered. It also sheds light on a lesser-studied geological epoch—the current one, the Holocene.

“We kept looking for this paper, and it didn’t exist,” said lead author Hannah Palmer, who recently earned her Ph.D. from the UC Davis Department of Earth and Planetary Sciences. “There are many records of past climate for a single location, but no one had put it all together to understand the big picture. So we decided to write it.”

The authors analyzed more than 40 published studies, examining the interplay among land and sea temperature, hydroclimate and fire activity across three distinct phases.

The study found:

  • Compared to pre-Holocene conditions (the last Glacial period), the Early Holocene (11,700-8,200 years ago) was a time of warm seas, a warm and dry Pacific Northwest, a warm and wet Southwest and fairly low fire activity.
  • By the Middle Holocene (8,200-4,200 years ago), that pattern had reversed: The ocean’s surface cooled, the Pacific Northwest became cool and wet, and the Southwest became drier.
  • The Late Holocene (4,200 years ago-present) is the most climatically variable period. It marks the period when the “modern” climate and temperature patterns were established. The study noted a defined interval of fire activity over the past two centuries that is linked to human activity.

Unprecedented interval

The study also considered the impact of humans on environmental changes at the time, noting that the Era of Colonization (1850-present) represents an unprecedented environmental interval in the climate records.

“Humans have been living here throughout the entire Holocene,” Palmer said. “The climate impacted them, and they impacted the climate, especially in recent centuries. This paper shows how that push and pull has changed over the past 11,000 years.”

Different responses

“Sometimes people point to recent rain or cold snaps as evidence against climate change,” said co-author Veronica Padilla Vriesman, a recent Ph.D. graduate from UC Davis Department of Earth and Planetary Sciences. “This study illustrates how different regions respond differently to global climate changes. That long-term perspective helps us understand the historical climate of the western U.S. and how it may respond moving forward.”

The study stemmed from a graduate seminar about the Holocene period led by Tessa Hill, a professor in the Department of Earth and Planetary Sciences and associate vice provost of Public Scholarship and Engagement. Additional co-authors include Caitlin Livsey and Carina Fish. All authors were part of Hill’s Ocean Climate Lab at the UC Davis Bodega Marine Laboratory in the Department of Earth and Planetary Sciences.

“Climate records from the Holocene provide a valuable window into the context of human-caused climate change,” said Hill. “They provide an opportunity for us to understand places that may be more or less resilient to change in the future.”

Hannah M. Palmer et al, Holocene climate and oceanography of the coastal Western United States and California Current System, Climate of the Past (2023). DOI: 10.5194/cp-19-199-2023