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Early earth: Arsenic and primordial life

Nature Geoscience Advanced Online - Sat, 10/25/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2275

Author: Thomas R. Kulp

Some modern microorganisms derive energy from the oxidation and reduction of arsenic. The association of arsenic with organic cellular remains in 2.7-billion-year-old stromatolites hints at arsenic-based metabolisms at the dawn of life.

Robust Arctic sea-ice influence on the frequent Eurasian cold winters in past decades

Nature Geoscience Advanced Online - Sat, 10/25/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2277

Authors: Masato Mori, Masahiro Watanabe, Hideo Shiogama, Jun Inoue & Masahide Kimoto

Over the past decade, severe winters occurred frequently in mid-latitude Eurasia, despite increasing global- and annual-mean surface air temperatures. Observations suggest that these cold Eurasian winters could have been instigated by Arctic sea-ice decline, through excitation of circulation anomalies similar to the Arctic Oscillation. In climate simulations, however, a robust atmospheric response to sea-ice decline has not been found, perhaps owing to energetic internal fluctuations in the atmospheric circulation. Here we use a 100-member ensemble of simulations with an atmospheric general circulation model driven by observation-based sea-ice concentration anomalies to show that as a result of sea-ice reduction in the Barents–Kara Sea, the probability of severe winters has more than doubled in central Eurasia. In our simulations, the atmospheric response to sea-ice decline is approximately independent of the Arctic Oscillation. Both reanalysis data and our simulations suggest that sea-ice decline leads to more frequent Eurasian blocking situations, which in turn favour cold-air advection to Eurasia and hence severe winters. Based on a further analysis of simulations from 22 climate models we conclude that the sea-ice-driven cold winters are unlikely to dominate in a warming future climate, although uncertainty remains, due in part to an insufficient ensemble size.

Evidence for arsenic metabolism and cycling by microorganisms 2.7 billion years ago

Nature Geoscience Advanced Online - Sat, 10/25/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2276

Authors: Marie Catherine Sforna, Pascal Philippot, Andrea Somogyi, Mark A. van Zuilen, Kadda Medjoubi, Barbara Schoepp-Cothenet, Wolfgang Nitschke & Pieter T. Visscher

The ability of microbes to metabolize arsenic may have emerged more than 3.4 billion years ago. Some of the modern environments in which prominent arsenic metabolism occurs are anoxic, as were the Precambrian oceans. Early oceans may also have had a relatively high abundance of arsenic. However, it is unclear whether arsenic cycling occurred in ancient environments. Here we assess the chemistry and nature of cell-like globules identified in salt-encrusted portions of 2.72-billion-year-old fossil stromatolites from Western Australia. We use Raman spectroscopy and X-ray fluorescence to show that the globules are composed of organic carbon and arsenic (As). We argue that our data are best explained by the occurrence of a complete arsenic cycle at this site, with As(III) oxidation and As(V) reduction by microbes living in permanently anoxic conditions. We therefore suggest that arsenic cycling could have occurred more widely in marine environments in the several hundred million years before the Earth’s atmosphere and shallow oceans were oxygenated.

Orbital forcing of the East Antarctic ice sheet during the Pliocene and Early Pleistocene

Nature Geoscience Advanced Online - Sat, 10/25/2014 - 23:00

Nature Geoscience. doi:10.1038/ngeo2273

Authors: M. O. Patterson, R. McKay, T. Naish, C. Escutia, F. J. Jimenez-Espejo, M. E. Raymo, S. R. Meyers, L. Tauxe & H. Brinkhuis

Heinz funded study: ‘Autism Linked to Man-Made Climate Change’

Climate Depot - Sat, 10/25/2014 - 18:01
http://guardianlv.com/2014/10/autism-linked-to-man-made-climate-change/

Study: ‘Bats are dying in unprecedented numbers at wind turbines’ – Published in PNAS

Climate Depot - Sat, 10/25/2014 - 17:51
http://www.pnas.org/content/111/42/15126.full

Paper: EXPOSED: How a shadowy network funded by foreign millions is making our household energy bills soar – for a low-carbon Britain

Climate Depot - Sat, 10/25/2014 - 17:41
http://www.dailymail.co.uk/news/article-2807849/EXPOSED-shadowy-network-funded-foreign-millions-making-household-energy-bills-soar-low-carbon-Britain.html

National Public Radio guts its climate reporting team

Climate Depot - Sat, 10/25/2014 - 13:52
We’re winning – National Public Radio guts its climate reporting team http://wattsupwiththat.com/2014/10/25/were-winning-national-public-radio-guts-its-climate-reporting-team From InsideClimate News: (hat tip to Michael E. Mann) By Katherine Bagley, InsideClimate News NPR has cut back on the number of staffers focused solely on the environment and climate change. Earlier this year, the news outlet had three full-time reporters and one [...]

Sea Ice Extent – Day 297 – Global Sea Ice Higher Than 1984 1986 1987 1991 1995 1997 and more

Climate Depot - Sat, 10/25/2014 - 11:11
Sea Ice Extent – Day 297 – Global Sea Ice Higher Than 1984 1986 1987 1991 1995 1997 and more http://sunshinehours.wordpress.com/2014/10/25/sea-ice-extent-day-297-global-sea-ice-higher-than-1984-1986-1987-1991-1995-1997-and-more – gReader Pro

New paper finds excuse #55 for the ‘pause’ in global warming: Reduced warming in N. Atlantic subpolar gyre – Published in Journal of Climate

Climate Depot - Sat, 10/25/2014 - 10:55
New paper finds excuse #55 for the ‘pause’ in global warming: Reduced warming in N. Atlantic subpolar gyre http://hockeyschtick.blogspot.com/2014/10/new-paper-finds-excuse-55-for-pause-in.html A paper published today in the Journal of Climate finds, “the sea level rise in the North Atlantic subpolar gyre developed at a reduced rate in the 2000s compared to rates in the 1990s” and “the heat [...]

Ocean data shows IPCC exaggerates anthropogenic global warming by factor of ~4.6 times – Published in Nature Geoscience

Climate Depot - Sat, 10/25/2014 - 08:57
Ocean data shows IPCC exaggerates anthropogenic global warming by factor of ~4.6 times http://hockeyschtick.blogspot.com/2014/10/ocean-data-shows-ipcc-exaggerates.html A paper published in Nature Geoscience attempts to explain away Trenberth’s “missing heat” as being “within uncertainty” of the dicey ocean heat content data. According to the authors, “We combine satellite data with ocean measurements to depths of 1,800 m, and show [...]

What About Those New EU CO2 Reduction Goals? Per The Numbers, Global Temps Not Impacted

Climate Depot - Sat, 10/25/2014 - 08:54
What About Those New EU CO2 Reduction Goals? Per The Numbers, Global Temps Not Impacted http://www.c3headlines.com/2014/10/eu-co2-reduction-goals-no-global-temp-impact-worthless-as-used-toilet-paper.html The EU elites and bureaucrats continue to beclown themselves…they are now going to pursue CO2 emission reductions that will accomplish zilch for the climate…. (click on image to enlarge) The EU members have just agreed to reducing, by 2030AD, [...]

New paper finds cooling, not warming, of mid- to upper troposphere increases likelihood of tropical cyclones – Published in Journal of Climate

Climate Depot - Sat, 10/25/2014 - 07:01
New paper finds cooling, not warming, of mid- to upper troposphere increases likelihood of tropical cyclones http://hockeyschtick.blogspot.com/2014/10/new-paper-finds-cooling-not-warming-of.html A paper published today in the Journal of Climate finds that cooling, not warming, of the mid- to upper troposphere increases the development of tropical cyclones. The mid- to upper troposphere mythical “hot spot” is predicted to warm [...]

Ex-EPA Chief May Have Lied To Congress

Climate Depot - Sat, 10/25/2014 - 06:47
http://dailycaller.com/2014/10/22/first-ever-epa-chief-may-have-lied-to-congress/2/

Report from UCLA: Michael Mann stunned when asked about Nobel prize fakery

Climate Depot - Sat, 10/25/2014 - 06:44
http://junkscience.com/2014/10/24/exclusive-report-from-ucla-michael-mann-stunned-when-asked-about-nobel-prize-fakery/

Film ‘Where the Boys Are’ Disproves Rising Seas Scare – ‘The beach is exactly as wide now as it was in 1960′

Climate Depot - Sat, 10/25/2014 - 06:42
http://newsbusters.org/blogs/pj-gladnick/2014/10/24/where-boys-are-disproves-rising-seas-scare

‘Warmer temperatures may cause more girl births’ – ‘New study forewarns an unexpected effect of climate change: more girl births than boy births’

Climate Depot - Sat, 10/25/2014 - 06:40
http://www.treehugger.com/natural-sciences/warmer-temperatures-may-cause-more-girl-births.html

‘Gender-sensitive approach’: Clueless bureaucrat’s dream: Trace CO2 attacks people who lack testicles, or something

Climate Depot - Sat, 10/25/2014 - 06:37
http://climate-l.iisd.org/news/policy-guide-on-mandates-and-entry-points-for-gender-equality-under-unfccc-published/
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