Changes in the sources of nitrogen and the composition of the phytoplankton community are more likely to account for the differences seen in the isotope data, Huckstadt said. “It looks more like a shift at the base of the food web, probably related to the transition from the Little Ice Age to current conditions, causing changes in the phytoplankton community,” he said.
See also: “Here we present new data from the Ross Sea, Antarctica, that indicates surface temperatures were ~ 2 °C colder during the LIA, with colder sea surface temperatures in the Southern Ocean and/or increased sea-ice extent, stronger katabatic winds, and decreased snow accumulation.”
Dans la lutte que mènent nos villes contre la pollution urbaine, on perçoit la recherche désespérée de solutions alternatives aux véhicules conventionnels. C’est le cas en particulier pour les particules fines, même s’il est de bon ton de passer sous silence que le chauffage contribue aussi largement à cette pollution….
To date, about 1.5 million species have been formally described in the scientific literature, most of them insects. Proportionally, bacteria comprise less than 1% of all described species.
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In a new paper published in The Quarterly Review of Biology (September 2017), researchers from the University of Arizona have estimated that there are roughly 2 billion living species on Earth, over a thousand times more than the current number of described species.
Banded iron formations were a prevalent feature of marine sedimentation ~3.8–1.8 billion years ago and they provide key evidence for ferruginous oceans. The disappearance of banded iron formations at ~1.8 billion years ago was traditionally taken as evidence for the demise of ferruginous oceans, but recent geochemical studies show that ferruginous conditions persisted throughout the later Precambrian, and were even a feature of Phanerozoic ocean anoxic events.
Currently (as of year 2007), human population on earth is 6.6 billion (via wikipedia). I went around to look for how much CO2 is exhaled out per person, and 2 claims were found (both via wikipedia)
Human appropriation of land for agriculture has greatly altered the terrestrial carbon balance, creating a large but uncertain car- bon debt in soils. Estimating the size and spatial distribution of soil organic carbon (SOC) loss due to land use and land cover change has been difficult but is a critical step in understand- ing whether SOC sequestration can be an effective climate mitigation strategy.
A natural global warming event that took place 56 million years ago was triggered almost entirely by volcanic eruptions that occurred as Greenland separated from Europe during the opening of the North Atlantic Ocean,
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The amount of carbon released during this time was vast—more than 30 times larger than all the fossil fuels burned to date and equivalent to all the current conventional and unconventional fossil fuel reserves we could feasibly ever extract.” Ridgwell said.
An unexpected finding was that enhanced organic matter burial was important in ultimately sequestering the released carbon and accelerating the recovery of the Earth’s ecosystem without massive extinctions.
Here’s another blow to the global warming alarmist scientists, who have been claiming that the Medieval Warm Period was a local, North Atlantic phenomenon, and did not really exist globally. What follows is a report on yet another paper contradicting this now worn out claim.
As the Houston flood disaster is unfolding, there is considerable debate about whether Hurricane Harvey was influenced by “global warming”. While such an issue matters little to the people of Houston, it does matter for our future infrastructure planning and energy policy.
Let’s review the two basic reasons why the Houston area is experiencing what now looks like a new record amount of total rainfall, at least for a 2-3 day period over an area of tens of thousands of square miles.
(…) “Nevertheless, we need to be clear that the changes in temperature are gradual, and that recovery can take hundreds of thousands of years. Given the rapid increase in the rate of global warming at present, this kind of wait is not an option for us”.
Our findings indicate that the water intrusion problems in the region are due not to “sea level rise”, but primarily to land subsidence due to groundwater depletion and, to a lesser extent, subsidence from glacial isostatic adjustment. We conclude that water intrusion will thus continue even if sea levels decline. These findings are critical because the water intrusion problems in the Chesapeake Bay—and elsewhere—cannot be successfully solved unless their causes are correctly identified and appropriate remedies are devised.
by Roger Andrews, August 23, 2017 in Energy Matters (blog)
Between 2007 and 2015 total annual US CO2 emissions decreased by 740 million tons (12%). An updated analysis shows that 35% of this decrease was caused by natural gas replacing coal in electricity generation, 30% by lower fuel consumption in the transportation sector, 28% by renewables replacing
There are models that predict that the interior of the East Antarctic ice sheet wouldn’t change very much, even if the West Antarctic ice sheet was taken away,” Licht said. According to these models, even if the ice sheet’s perimeter retreats, its core remains stable.
We suggest that solar activity may play a key role in driving the climatic fluctuations in North China during the last 22 centuries, with its quasi ∼100, 50, 23, or 22-year periodicity clearly identified in our climatic reconstructions.
We quantitatively illustrate that precipitation (67.4%) may have been more important than temperature (32.5%)…
La comparaison des fluctuations du CO2 atmosphérique retracées à partir de ces estimations avec des courbes des changements de température a révélé de fortes baisses du CO2 atmosphérique (200-300 ppm), couplées à de fortes hausses de la température moyenne à la surface du globe (5-8°C) à l’échelle de quelques millions d’années.
(…) Maximum sustained winds are near 110 mph (175 km/h) with higher gusts. Some strengthening is possible, and Harvey is forecast to become a major hurricane before it reaches the middle Texas coast (…)
by Ron Clutz, August 25, 2017 in ClimateChangeDispatch
The animated image shown after the jump shows ice extents for day 233 from 2007 to 2017. Particularly interesting is the variation in the CAA (Canadian Arctic Archipelago), crucial for the Northwest Passage
What is causing the death of the polar bear as a climate change icon? Fat bears are part of it, but mostly it’s the fact that polar bear numbers haven’t declined as predicted.
Sea level changes is a key issue in the global warming scenario. It has been widely claimed that sea is rising as a function of the late 20th’s warming pulse. Global tide gauge data sets may vary between +1.7 mm/yr to +0.25 mm/yr depending upon the choice of stations. At numerous individual sites, available tide gauges show variability around a stable zero level …
… In this situation, it is recommended that we return to the observational facts, which provides global sea level records varying between ±0.0 and +1.0 mm/yr; i.e. values that pose no problems in coastal protection.
The sun was completely free of spots on 11 days in July. Notable: while during last month the sun’s northern hemisphere was more active (in June all sunspots were in the northern hemisphere), last month the southern hemisphere was the most active part with 60% of the sunspots appearing there. The following diagram shows the course of solar cycle 24 thus far (…)
by James E Kamis, August 23, in ClimateChangeDispatch
The now three-year-old Plate Climatology Theory is on the brink of total confirmation. This is the result of two just-released and very telling Antarctic research studies. Combining the results of these two studies with the massive amounts of pre-existing data it is possible to show with very high certainty that melting of West Antarctic glaciers is directly related to bedrock heat flow and chemically charged heated fluid flow from the 5,000-mile-long West Antarctic Rift System (see Figure 1).
La géologie, une science plus que passionnante … et diverse
