Scientist Colin Blakemore visits a creationist museum in Kentucky.
NASA scientists recorded the biggest explosion from a meteorite impact seen on the moon in eight years of monitoring.
The lunar burst was caused by a 40-kilogram boulder-sized rock slamming into the surface at about 90,000 kph. It generated a flash 10 times brighter than anything seen before, which came from the thermal glow of molten rock at the point of impact.
In these days of continually streaming propaganda over nearly any politically sensitive issue, the subject of climate change has become so entangled with local and national political interests that it is good to step back and look at what the science is really saying, again.
Today Science magazine published a paper that presented analyses of lake sediments from a north-east Russian lake:
Understanding the evolution of Arctic polar climate from the protracted warmth of the middle Pliocene into the earliest glacial cycles in the Northern Hemisphere has been hindered by the lack of continuous, highly resolved Arctic time series. Evidence from Lake El’gygytgyn, NE Arctic Russia, shows that 3.6-3.4 million years ago, summer temperatures were ~8°C warmer than today when pCO2 was ~400 ppm. Multiproxy evidence suggests extreme warmth and polar amplification during the middle Pliocene, sudden stepped cooling events during the Pliocene-Pleistocene transition, and warmer than present Arctic summers until ~2.2 Ma, after the onset of Northern Hemispheric glaciation. Our data are consistent with sea-level records and other proxies indicating that Arctic cooling was insufficient to support large-scale ice sheets until the early Pleistocene.
From the press release:
The Arctic was very warm during a period roughly 3.5 to 2 million years ago—a time when research suggests that the level of carbon dioxide in the atmosphere was roughly comparable to today’s—leading to the conclusion that relatively small fluctuations in carbon dioxide levels can have a major influence on Arctic climate, according to a new analysis of the longest terrestrial sediment core ever collected in the Arctic.
“One of our major findings is that the Arctic was very warm in the middle Pliocene and Early Pleistocene—roughly 3.6 to 2.2 million years ago—when others have suggested atmospheric carbon dioxide was not much higher than levels we see today,” said Julie Brigham-Grette, of the University of Massachusetts Amherst.
She added that “this could tell us where we are going in the near future. In other words, the Earth system response to small changes in carbon dioxide is bigger than suggested by earlier climate models.”
The lake being examined is north of the Arctic Circle.
It is important to remember the phrase Polar Amplification. This lake evidence is just one more in a long list that indicates that the climate will change more significantly towards the poles of the planet. This is why an island in the Pacific, say Hawaii, will experience much less temperature change than the north side of Greenland.
As noted in today’s article in Scientific American, 400 PPM: Carbon Dioxide in the Atmosphere Reaches Prehistoric Levels:
The last time CO2 levels at Mauna Loa were this high [400 ppm], Homo sapiens did not live there. In fact, the last time CO2 levels are thought to have been this high was more than 2.5 million years ago, an era known as the Pliocene, when the Canadian Arctic boasted forests instead of icy wastes. The land bridge connecting North America and South America had recently formed. The globe’s temperature averaged about 3 degrees C warmer, and sea level lapped coasts 5 meters or more higher.
While the Science paper is behind a pay-wall, the supplemental material is not. Among the information that impressed me was the graph of vegetation changes (from pollen):
In that diagram we can see how the transition from the warmer Pliocene (on the right of the diagram) to the Pleistocene (the “Ice Age”, on the left of the diagram) was accompanied by a change in vegetation. There is no doubt that climate change does indeed change the biome.
Whether we are discussing changes in ecosystems or sea level, it is important to remember that we humans have such a short life and even shorter attention span that large changes are often just overlooked if we rely upon casual glances at the world around us. As common in all areas of science, only careful and systematic observations and analyses can take us out of our biases and “common sense” to gain a greater knowledge of the world around us.
That appears, though, by looking at our popular press and current political environment, to be quite a challenge for us today. There has been no substantive change in the production of CO2 in our modern industrialized world. Growth in CO2 output continues with only modest slowing during the deepest of economic recessions.
What will it take to change our way?
A look back at the best views of our planet from space in the last year, including true color satellite images, Earth science data visualizations, time lapses from the International Space Station, and computer models.
NPP “Blue Marble”
Time-lapse from International Space Station
NPP daytime view followed by night views
River Outflow to the Kara Sea
Bylot Island Comparison
Crop Circles in the Desert
Crack in the Pine Island Glacier
Tiny Shrimp, Big Changes
Petermann Ice Island 2012
United States Active Fires 2012
Gulf Stream Sea Surface Currents and Temperatures
Daily 2012 ozone hole
Daily Sea Ice during Aug & Sept 2012 with Winds
Circulation of Ocean Currents around the Western Antarctic Ice Shelves
Hurricane Sandy’s winds
Aerosols from GEO-5 Nature Run Collection
Moonset time-lapse from International Space Station
This video is public domain and can be downloaded at: svs.gsfc.nasa.gov
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After cruising through space for who knows how many millennia, a chunk of rock about 15 meters across plunged into Earth’s atmosphere above the Russian region of Chelyabinsk today and exploded with a force rivaling a nuclear blast, injuring at least 700 people with its shockwave: Russian Meteor Largest in a Century.
A meteor that exploded over Russia this morning was the largest recorded object to strike the Earth in more than a century, scientists say. Infrasound data collected by a network designed to watch for nuclear weapons testing suggests that today’s blast released hundreds of kilotonnes of energy. That would make it far more powerful than the nuclear weapon tested by North Korea just days ago and the largest rock crashing on the planet since a meteor broke up over Siberia’s Tunguska river in 1908.
“It was a very, very powerful event,” says Margaret Campbell-Brown, an astronomer at the University of Western Ontario in London, Canada, who has studied data from two infrasound stations near the impact site. Her calculations show that the meteoroid was approximately 15 metres across when it entered the atmosphere, and put its mass at around 40 tonnes. “That would make it the biggest object recorded to hit the Earth since Tunguska,” she says.
The meteor appeared at around 09:25 a.m. local time over the region of Chelyabinsk, near the southern Ural Mountains. The fireball blinded drivers and a subsequent explosion blew out windows and damaged hundreds of buildings. So far, more than 700 people are reported to have been injured, mainly from broken glass, according to a statement from the Russian Emergency Ministry.
The unsettling part of the story is that nobody saw it coming — and we probably won’t see the next one either.
Despite its massive size, the object went undetected until it hit the atmosphere. “I’m not aware of anyone who saw this coming,” says Heiner Klinkrad, head of the European Space Agency’s space debris office at the European Space Operations Centre in Darmstadt, Germany. Although a network of telescopes watches for asteroids that might strike Earth, it is geared towards spotting larger objects — between 100 metres and a kilometre in size.
“Objects like that are nearly impossible to see until a day or two before impact,” says Timothy Spahr, Director of the Minor Planet Center in Cambridge, Massachusetts, which tracks asteroids and small bodies. So far as he knows, he says, his centre also failed to spot the approaching rock.
We have another Martian Mystery Object — this one a thing that looks suspiciously like a hunk of metal. Curiosity detected it, through a high-res image taken from its Mastcam, on Sol 173 (January 30 in Earth days). Universe Today calls the object “a small metallic-looking protuberance” — it resembles a thick, bent nail, sticking out of the Martian surface — and it is visible in part because it projects a tiny little shadow on the rock below.
For the heck of it, and because it’s a slow news day, I imported the original full-sized photo into Fireworks CS6, clipped out the metallic object, zoomed way in using the Bicubic smoothing algorithm, and here’s the result:
A few days ago LGF and I got into a bit of a squabble with renowned climate change denier Marc Morano over an error I made concerning his “debate” with Bill Nye. I wrote that he used a talking point often trotted out by the denialists (and found on Morano’s site in several places), during that debate. He didn’t say it. At least during the debate.
Although Morano did not use that talking point in this “debate,” and complained bitterly about my claim that he had, (no doubt to direct attention away from the substance of my post) he did throw out quite a few other howlers.