knocker
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Posts posted by knocker
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Minus credibility? Antarctic record low temperature disputed
American scientists claim they have found the coldest place on Earth - in Antarctica, where temperatures can fall below -91C. One Russian scientist calls this into question, pointing out the new record was made using remote measurements.
American researchers from the US National Snow and Ice Data Centre (NSIDC) prepare to make public satellite temperature measurements data which maintains that a record temperature of -91.2°C was registered in Antarctica on August 3, 2004, near the Japanese Dome Fuji station, situated on the Valkyrie Dome in the heart of the White Continent.
The preface of the report prepared for the American Geophysical Union's annual meeting in San Francisco suggests that the space-borne Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors aboard NASA’s satellites registered the record low temperature “during periods of extensive clear sky conditions†nearly a decade ago “along the highest section of the East Antarctic ice divide.â€
The report also maintains that the “winters of 1997, 2001, 2003, and 2004 showed several temperature minima below -90°C.â€
“It is likely that record cold sites identified by the data have small areas within them that are significantly colder than the grid cell mean,' a published summary of the findings said.
So far the lowest temperature was also measured in Antarctica, at the then-Soviet Vostok station, where during the winter of 1983 a record –89.2°C was officially registered.
http://rt.com/news/antarctica-temperature-record-questioned-922/
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If I'm getting your meaning correctly GW the 500MB height above mean sea level is dependent on pressure and temperature. Initially you calculate the 1000MB height using the surface pressure and temperature. If the pressure is below 1000mb it will be negative. Then the temperature profile is used between 1000MB-500MB to calculate the thickness between the two levels. The two are then added together to obtain the 500MB height.
Thus the colder the layer the lower the height and vice versa. The same applies to the surface pressure. To answer your question a surface pressure anomaly would effect the height but I would think it would be very small depending on the size of the anomaly of course.
In the old days this was calculated by hand using a thermodynamic diagram, I wish I had a pound for the times I've done this, but I assume these days they use the equations. I would repress the urge to go there. Hope this helps.
I missed out a piece of the calculation. When I said then the temperature profile is used between 1000MB-500MB to calculate the thickness between the two levels i meant between successive levels up to 500MB. So 1000-900, 900-850, 850-800, 800-700, 700-600 and then 600-500 and the add them all together. This of course gives you the height for each level.
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Bit out of date, huh?
I take it from that you are saying the paper has no validity as it's three years old, huh? In that case we had better ignore any papers published before last week.
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Another Study posing the question of a link between Arctic melt and weather impacts further south.
EDIT: and this;
I'm still not quite getting my head around the 500hpa temp drops paper?
Am I right in thinking that the physical height you find this pressure at varies with surface pressure and so temps might vary if we saw certain pressure anoms at ground level?
If I'm getting your meaning correctly GW the 500MB height above mean sea level is dependent on pressure and temperature. Initially you calculate the 1000MB height using the surface pressure and temperature. If the pressure is below 1000mb it will be negative. Then the temperature profile is used between 1000MB-500MB to calculate the thickness between the two levels. The two are then added together to obtain the 500MB height.
Thus the colder the layer the lower the height and vice versa. The same applies to the surface pressure. To answer your question a surface pressure anomaly would effect the height but I would think it would be very small depending on the size of the anomaly of course.
In the old days this was calculated by hand using a thermodynamic diagram, I wish I had a pound for the times I've done this, but I assume these days they use the equations. I would repress the urge to go there. Hope this helps.
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I wouldn't use the word 'catastrophic' but there has been in my opinion one significant change that is already having an effect. That is greater storm surges and sea level rise. One example where the actual storm played a lesser role.
https://www2.ucar.edu/atmosnews/opinion/8585/dissecting-sandys-surge
http://science.time.com/2013/10/29/a-year-after-sandy-living-dangerously-by-the-sea/
http://www.scientificamerican.com/article.cfm?id=how-to-protect-new-york-city-from-storm-surges
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Understanding sea level: Ways forward from the past
http://www.pages-igbp.org/download/docs/newsletter/2009-2/PAGESnews-2009-2_low-res.pdf
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Very little cloud.
1028 falling
Temp 7.5C
Calm
Excellent vis.
Another two months of this would be ideal.
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I think there is case to be made that multinational companies run the world.
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Here we go again. Reducing the use of fossil fuels? Not significantly in my lifetime.
By US estimates, the Arctic may hold 13 per cent of the world’s undiscovered oil and 30 per cent of its untapped gas as well as untold mineral resources. The London-based think-tank Chatham House talks of an Arctic “cold rushâ€. Greenland, a frozen and mostly empty sprawl of a country reaching up from the Atlantic to the Arctic Ocean, sees a chance to reclaim its pre-colonial identity. “I guess we are in the business of nation-building,†says Vittus Qujaukitsoq, the minister of economy in a government with its sights on independence.http://www.ft.com/cms/s/2/8c2b6a12-5c71-11e3-931e-00144feabdc0.html#axzz2muNSPQDH
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There is a bit more on that here Dev.
http://forum.netweather.tv/topic/78379-air-pollution-killing-over-two-million-annually/#entry2857422
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And then there’s the energy imbalance
There are a few things I have been considering writing about, but since I’ve renamed the blog to be more explicitly physics orientated, I thought the first should at least reflect that change. There’s a recent paper by James Hansen – and 17 co-authors – called Assessing ‘‘Dangerous Climate Change’’: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature. It’s an interesting paper because it discusses both the scientific evidence for global warming/climate change and considers various policy options (violating what many would regard as a fundamental rule – I don’t though). The paper’s been discussed in a number of other places already (here, and here for example), but I was going to discuss one very basic thing that I think it covers very well.
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Abstract
Recent analyses of sediment samples from “black mat†sites in South America and Europe support previous interpretations of an ET impact event that reversed the Late Glacial demise of LGM ice during the Bølling Allerød warming, resulting in a resurgence of ice termed the Younger Dryas (YD) cooling episode. The breakup or impact of a cosmic vehicle at the YD boundary coincides with the onset of a 1-kyr long interval of glacial resurgence, one of the most studied events of the Late Pleistocene. New analytical databases reveal a corpus of data indicating that the cosmic impact was a real event, most possibly a cosmic airburst from Earth's encounter with the Taurid Complex comet or unknown asteroid, an event that led to cosmic fragments exploding interhemispherically over widely dispersed areas, including the northern Andes of Venezuela and the Alps on the Italian/French frontier. While the databases in the two areas differ somewhat, the overall interpretation is that microtextural evidence in weathering rinds and in sands of associated paleosols and glaciofluvial deposits carry undeniable attributes of melted glassy carbon and Fe spherules, planar deformation features, shock-melted and contorted quartz, occasional transition and platinum metals, and brecciated and impacted minerals of diverse lithologies. In concert with other black mat localities in the Western USA, the Netherlands, coastal France, Syria, Central Asia, Peru, Argentina and Mexico, it appears that a widespread cosmic impact by an asteroid or comet is responsible for deposition of the black mat at the onset of the YD glacial event. Whether or not the impact caused a 1-kyr interval of glacial climate depends upon whether or not the Earth had multiple centuries-long episodic encounters with the Taurid Complex or asteroid remnants; impact-related changes in microclimates sustained climatic forcing sufficient to maintain positive mass balances in the reformed ice; and/or inertia in the Atlantic thermohaline circulation system persisted for 1 kyr.
http://onlinelibrary.wiley.com/doi/10.1111/geoa.12033/abstract
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Reducing Salt Is Bad for Glacial Health, NASA Finds
A new NASA-led study has discovered an intriguing link between sea ice conditions and the melting rate of Totten Glacier, the glacier in East Antarctica that discharges the most ice into the ocean. The discovery, involving cold, extra salty water -- brine -- that forms within openings in sea ice, adds to our understanding of how ice sheets interact with the ocean, and may improve our ability to forecast and prepare for future sea level rise.
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If you think it's cold in the U.S. look what the wind chills were yesterday morning in SK, Canada
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Quite interesting.
Knowing the unknowns
AbstractThe Earth's atmosphere is not the only source of radiative forcing and anthropogenic climate change. As surely as people and civilizations have carbon footprints, they have albedo footprints as well. By altering the reflectivity of roughly half the land surface of the Earth in the past, mankind has made inadvertent geoengineering a part of the landscape of history. This worldwide alteration of reflectivity raises questions about the future of climate change, for albedo is a first-order determinant of the Earth's radiative equilibrium. As surfaces absorb roughly 100 times more solar energy than the atmosphere, future anthropogenic changes in both land and water albedo may figure significantly in climate policy outcomes.
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Sadly Knocks the latest posting 'over there' would seem to show they have difficulties distinguishing between 'plots'........?
I
I think it's called losing the plot GW. Yes interesting article but i would imagine there will be a number of, shall we say, complications down the road.
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So, which of the generic Anything But Carbon dismissals will be used for this?
- It's just conjecture â–¡
- Something to do with grant moneyâ–¡
- Lefty propaganda â–¡
- Shifting goalposts â–¡
- Something to do with the hockey stick â–¡
- Global Warming stopped in '97, '98, '05, '10 â–¡
- Al Gore â–¡
- Other â–¡
- All of the above â–¡
Or maybe a self proclaimed AGW sceptic will carefully review the article and produce a thorough, science and evidence based rebuttal?
Could be a Marxist plot?
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An apparent hiatus in global warming?
Kevin E. Trenberth and John T. Fasullo
AbstractGlobal warming first became evident beyond the bounds of natural variability in the 1970s, but increases in global mean surface temperatures have stalled in the 2000s. Increases in atmospheric greenhouse gases, notably carbon dioxide, create an energy imbalance at the top-of-atmosphere (TOA) even as the planet warms to adjust to this imbalance, which is estimated to be 0.5–1 W m−2 over the 2000s. Annual global fluctuations in TOA energy of up to 0.2 W m−2 occur from natural variations in clouds, aerosols, and changes in the Sun. At times of major volcanic eruptions the effects can be much larger. Yet global mean surface temperatures fluctuate much more than these can account for. An energy imbalance is manifested not just as surface atmospheric or ground warming but also as melting sea and land ice, and heating of the oceans. More than 90% of the heat goes into the oceans and, with melting land ice, causes sea level to rise. For the past decade, more than 30% of the heat has apparently penetrated below 700 m depth that is traceable to changes in surface winds mainly over the Pacific in association with a switch to a negative phase of the Pacific Decadal Oscillation (PDO) in 1999. Surface warming was much more in evidence during the 1976–1998 positive phase of the PDO, suggesting that natural decadal variability modulates the rate of change of global surface temperatures while sea-level rise is more relentless. Global warming has not stopped; it is merely manifested in different ways.
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Shanghai Orders Cars Off Roads as Pollution Exceeds Scale
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http://forum.netweather.tv/topic/76448-scepticism-of-man-made-climate-change/page-43#entry2857337
I see the camp followers at WUWT are out for the weekend and having hystrerics. Sad sacks just about covers it. Frankly I thought it a bit pathetic. Frankly I think they give genuine skeptics a bad name if anyone is daft enough to take any notice.
Denier weirdness: This is Denialism at WUWT
Deniers are in hysterics and over the moon, tickled pink with a "funny" video Anthony Watts dug up from somewhere or other (archived here). It's supposed to be a skit on the SkepticalScience escalator. The video shows the escalator with global surface temperature, then zooms out to to show temperatures going back about 12,000 years. Only thing is...Well, I'll let you see for yourself. This isn't the whole video, just a short segment plus a bit I added. In fact it's my very first ever YouTube video. In fact I think it's the very first video I have ever produced or the first published at least. (I might have played around with one a couple of decades ago.) It's just a slight edit of the one at WUWT, but I don't think anyone will mind too much seeing it's mainly charts of SkepticalScience and elsewhere.
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Met Office scientist recognised as 'global thinker'
Dr Peter Stott has been selected as one of Foreign Policy magazine's Global Thinkers of 2013 for his work on the report Explaining Extreme Events of 2012 from a Climate Perspective.
He shares the recognition with his fellow editors on the publication - Thomas Peterson, Martin Hoerling, and Stephanie Herring, who are all based at the National Oceanic and Atmospheric Administration (NOAA) in the US.
Together they have played a leading role in pioneering climate attribution studies, which aim to assess how human-induced climate change has altered the chances of specific extreme weather events happening.
In the Explaining Extreme Events of 2012 report, climate scientists from around the world analysed 12 extreme events and found evidence for a 'human fingerprint' in half of them.
Dr Stott said: "Extreme or unusual weather and climate-related events can have major impacts across the world and there is a huge demand to understand how human influence is changing the risks we face.
http://www.metoffice.gov.uk/news/releases/archive/2013/global-thinker
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Lol, ignoring your remarks about my ego ( humour really ) what the MetO has to say as a causation is pretty damming in their own defence of the theory.
I must admit I find that a bit odd after you have said.
"I'll go with what the MetO and the official sources say not some fudged data young man",
Have they fallen out of favour already young man?
Anyway
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Boys! (all of you) calm down and be nice to one another
I'm perfectly calm, which is quite remarkable in the face of such a remarkable ego. The arrogant manner in which the undisputed rise in temps since the Industrial Revolution, rise in sea levels, glaciers melting, ice sheet mass balance loss over 150 odd years is casually dismissed, and NASA accused of fudging the figures, beggars belief. And just for the record I'm not the who has accused NASA of fudging the data without any supporting evidence.
And unlike SI I have read what the METO had to say. Hope he doesn't mind a link.
Concluding remarksWhat can we conclude from all this? First, periods of slowing down and pauses in surface warming are not unusual in the instrumental temperature record. Second, climate model simulations suggest that we can expect such a period of a decade or more to occur at least twice per century, due to internal variability alone. Third, recent research suggests that ocean heat re-arrangements, with a contribution from changes in top of the atmosphere radiation,could be important for explaining the recent pause in global surface warming.We note, however, the need for better continuous long-term records of the net radiation at the top of the atmosphere in general, and of solar radiation in particular to understand decadal changes in global climate. We also need to maintain and extend to deeper levels(below 2000m) the monitoring of the heat content and thermal structure of the oceans by in situ measurements, building on the tremendous advances made in recent years with the introduction of Argo floats,and the constraints using the sea level measurements from satellites and tide gauges.Finally we note the importance of understanding the dynamics ofthe global oceans, and how this acts to rearrange heat within the system. Of particular relevance here is a greater understanding of decadal variability in the Pacific Ocean.The scientific questions posed by the current pause in global surface warming require us to understand in much greater detail the flows of energy into, out of, and around the Earth system. Current observations are not detailed enough or of long enough duration to provide definitive answers on the causes of the recent pause, and therefore do note enable us to close the Earth’s energy budget. These are major scientific challenges that the research community is actively pursuing, drawing on exploration and experimentation using a combination of theory, models and observations.http://www.metoffice.gov.uk/media/pdf/q/0/Paper2_recent_pause_in_global_warming.PDF
Best summed up.........
But you are right Tamara. Time to draw a line under this exercise in futility.
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I'll ignore your usual patronizing. So NASA has fudged the data which no doubt you can explain. Any thoughts on the pause mid-century before the warming started again. Maybe natural cycles suppressing CO2 forcing? Or maybe not. And why did the warming suddenly take off again? I see we are back from 20 to 17 years. It really is a moveable feast.
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Bizarre creatures from the Antarctic abyss discovered by Cambridge scientists
in Space, Science & nature
Posted · Edited by knocker
For a minute there I thought this was about the skeptic thread.
http://www.cambridge-news.co.uk/News/SLIDESHOW-Bizarre-creatures-from-the-Antarctic-abyss-discovered-by-Cambridge-scientists-20131209060609.htm