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US-Canadian partnership for isotopes

World Nuclear News - Mon, 02/23/2015 - 10:25
A Canadian-US partnership has been announced to create a "new, reliable supply" of medical isotopes for use worldwide.

Willie Soon must be doing something right

Climate Depot - Mon, 02/23/2015 - 10:21

RPV installation work starts at Novovoronezh 7

World Nuclear News - Mon, 02/23/2015 - 09:57
Russian architect-engineer AtomEnergoProekt has started work to install the reactor pressure vessel of the second unit of the Novovoronezh II nuclear power plant.

Palaeoclimate: A glacial zephyr

Nature Geoscience Advanced Online - Mon, 02/23/2015 - 00:00

Nature Geoscience. doi:10.1038/ngeo2377

Author: Aaron E. Putnam

The hydrology of the North American west looked very different at the Last Glacial Maximum to today. A model–data comparison suggests the observed precipitation patterns are best explained if the storm track was squeezed and steered by high-pressure systems.

Transport of metals and sulphur in magmas by flotation of sulphide melt on vapour bubbles

Nature Geoscience Advanced Online - Mon, 02/23/2015 - 00:00

Nature Geoscience. doi:10.1038/ngeo2373

Authors: J. E. Mungall, J. M. Brenan, B. Godel, S. J. Barnes & F. Gaillard

Emissions of sulphur and metals from magmas in Earth’s shallow crust can have global impacts on human society. Sulphur-bearing gases emitted into the atmosphere during volcanic eruptions affect climate, and metals and sulphur can accumulate in the crust above a magma reservoir to form giant copper and gold ore deposits, as well as massive sulphur anomalies. The volumes of sulphur and metals that accumulate in the crust over time exceed the amounts that could have been derived from an isolated magma reservoir. They are instead thought to come from injections of multiple new batches of vapour- and sulphide-saturated magmas into the existing reservoirs. However, the mechanism for the selective upward transfer of sulphur and metals is poorly understood because their main carrier phase, sulphide melt, is dense and is assumed to settle to the bottoms of magma reservoirs. Here we use laboratory experiments as well as gas-speciation and mass-balance models to show that droplets of sulphide melt can attach to vapour bubbles to form compound drops that float. We demonstrate the feasibility of this mechanism for the upward mobility of sulphide liquids to the shallow crust. Our work provides a mechanism for the atmospheric release of large amounts of sulphur, and contradicts the widely held assumption that dense sulphide liquids rich in sulphur, copper and gold will remain sequestered in the deep crust.

Declining uncertainty in transient climate response as CO2 forcing dominates future climate change

Nature Geoscience Advanced Online - Mon, 02/23/2015 - 00:00

Nature Geoscience. doi:10.1038/ngeo2371

Authors: Gunnar Myhre, Olivier Boucher, François-Marie Bréon, Piers Forster & Drew Shindell

Carbon dioxide has exerted the largest portion of radiative forcing and surface temperature change over the industrial era, but other anthropogenic influences have also contributed. However, large uncertainties in total forcing make it difficult to derive climate sensitivity from historical observations. Anthropogenic forcing has increased between the Fourth and Fifth Assessment Reports of the Intergovernmental Panel of Climate Change (IPCC; refs , ), although its relative uncertainty has decreased. Here we show, based on data from the two reports, that this evolution towards lower uncertainty can be expected to continue into the future. Because it is easier to reduce air pollution than carbon dioxide emissions and because of the long lifetime of carbon dioxide, the less uncertain carbon dioxide forcing is expected to become increasingly dominant. Using a statistical model, we estimate that the relative uncertainty in anthropogenic forcing of more than 40% quoted in the latest IPCC report for 2011 will be almost halved by 2030, even without better scientific understanding. Absolute forcing uncertainty will also decline for the first time, provided projected decreases in aerosols occur. Other factors being equal, this stronger constraint on forcing will bring a significant reduction in the uncertainty of observation-based estimates of the transient climate response, with a 50% reduction in its uncertainty range expected by 2030.

Steering of westerly storms over western North America at the Last Glacial Maximum

Nature Geoscience Advanced Online - Mon, 02/23/2015 - 00:00

Nature Geoscience. doi:10.1038/ngeo2365

Authors: Jessica L. Oster, Daniel E. Ibarra, Matthew J. Winnick & Katharine Maher

The hydroclimate history of North America includes the formation and desiccation of large inland lakes and the growth and ablation of glaciers throughout the Quaternary period. At the Last Glacial Maximum, expanded pluvial lakes in the south and aridity in the northwest suggest that the winter westerly storm track was displaced southwards and migrated northwards as the Laurentide Ice Sheet waned. However, lake highstands do not occur synchronously along zonal bands, in conflict with this hypothesis. Here we compile a network of precipitation proxy reconstructions from lakes, speleothems, groundwater deposits, packrat middens and glaciers from the western and southwestern US, which we compare with an ensemble of climate simulations to identify the controls of regional hydroclimatic change. The proxy records suggest a precipitation dipole during the Last Glacial Maximum, with wetter than modern conditions in the southwest and drier conditions near the ice sheet, and a northwest–southeast trending transition zone across the northern Great Basin. The models that simulate a weaker and south-shifted Aleutian low-pressure system, a strong North Pacific high-pressure system, and a high above the ice sheet best reproduce this regional variation. We therefore conclude that rather than a uniformly south-shifted storm track, a stronger jet that is squeezed and steered across the continent by high-pressure systems best explains the observed regional hydroclimate patterns of the Last Glacial Maximum.

High Poisson's ratio of Earth's inner core explained by carbon alloying

Nature Geoscience Advanced Online - Mon, 02/23/2015 - 00:00

Nature Geoscience. doi:10.1038/ngeo2370

Authors: C. Prescher, L. Dubrovinsky, E. Bykova, I. Kupenko, K. Glazyrin, A. Kantor, C. McCammon, M. Mookherjee, Y. Nakajima, N. Miyajima, R. Sinmyo, V. Cerantola, N. Dubrovinskaia, V. Prakapenka, R. Rüffer, A. Chumakov & M. Hanfland

Geochemical, cosmochemical, geophysical, and mineral physics data suggest that iron (or iron–nickel alloy) is the main component of the Earth’s core. The inconsistency between the density of pure iron at pressure and temperature conditions of the Earth’s core and seismological observations can be explained by the presence of light elements. However, the low shear wave velocity and high Poisson’s ratio of the Earth’s core remain enigmatic. Here we experimentally investigate the effect of carbon on the elastic properties of iron at high pressures and temperatures and report a high-pressure orthorhombic phase of iron carbide, Fe7C3. We determined the crystal structure of the material at ambient conditions and investigated its stability and behaviour at pressures up to 205 GPa and temperatures above 3,700 K using single-crystal and powder X-ray diffraction, Mössbauer spectroscopy, and nuclear inelastic scattering. Estimated shear wave and compressional wave velocities show that Fe7C3 exhibits a lower shear wave velocity than pure iron and a Poisson’s ratio similar to that of the Earth’s inner core. We suggest that carbon alloying significantly modifies the properties of iron at extreme conditions to approach the elastic behaviour of rubber. Thus, the presence of carbon may explain the anomalous elastic properties of the Earth’s core.

Canadian Coast Guard working to free ship trapped on Lake Erie

Climate Depot - Sun, 02/22/2015 - 17:59

Author of NYTimes skeptic smear Justin Gillis ADMITTED he is a crusader for warmism

Climate Depot - Sun, 02/22/2015 - 10:24
On the East Anglia emails that were released in 2009 Gillis makes a strong statement: One was forced to read the e-mails and ask, “Do they suggest any sort of scientific misconduct?” As we studied them, it became clear to me that they didn’t, so we asked ourselves, “How do we respond in this situation [...]

Why was media silent? Flashback NASA’s James Hansen Received $250,000 from partisan Heinz Foundation & Endorsed Dem. John Kerry for Pres. in 2004

Climate Depot - Sun, 02/22/2015 - 07:40
1) EPW Report on Hansen – July 11, 2006 Hansen Received $250,000 from partisan Heinz Foundation & Endorsed Dem. John Kerry for Pres. in 2004 Excerpt: For example, Brokaw presents NASA’s James Hansen as an authority on climate change without revealing to viewers the extensive political and financial ties that Hansen has to Democrat Party partisans. Hansen, the director [...]

Woods Hole Oceanographic outfit literally swims in funds from Saudi oil company

Climate Depot - Sat, 02/21/2015 - 22:27

Flashback: ‘Collusion': Emails expose NYT reporter Justin Gillis ‘as an activist posing as a journalist, sneering at [MIT’s]Lindzen’

Climate Depot - Sat, 02/21/2015 - 22:10
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