Dr. Ricky Rood's Climate Change Blog |
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| Posted by: Dr. Ricky Rood, 21. helmikuuta 2012 klo 07:10 (GMT) | +11 |
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I'm a professor at U Michigan and lead a course on climate change problem solving. These articles include ideas from the course. And no tuition!
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LiveScience StaffDate: 01 March 2012 Time: 09:31 AM ET
The oldest and thickest Arctic ice seems to be vanishing faster than the younger, thinner ice at the edges of the Arctic Ocean's floating ice cap, a new NASA study finds.
Typically the thicker, older ice survives through the summer melt season (hence, it's called multi-year ice), while the younger ice that forms over the winter melts as quickly as it formed. That's what makes this new finding worrisome; if the ice that usually sticks around is rapidly disappearing, the Arctic sea ice is more vulnerable to further disappearance during the summer, said study researcher Joey Comiso, senior scientist at NASA Goddard Space Flight Center, Greenbelt, Md.
In the new study, Comiso and colleagues looked at multi-year ice that had made it through at least two summers. They wanted to see how it diminished with each passing winter over the past three decades. Results showed that the extent of multi-year ice, which includes areas of the Arctic Ocean where multi-year ice covers at least 15 percent of the water's surface, is shrinking at a rate of 15.1 percent per decade.
They found more disturbing results when looking at the "area" of the multi-year ice, which includes exclusively regions of the Arctic Ocean that are completely covered by multi-year ice. This sea-ice area is always smaller than sea-ice extent. They found that multi-year ice area is shrinking even faster than multi-year ice extent, by 17.2 percent per decade.
"The average thickness of the Arctic sea ice cover is declining because it is rapidly losing its thick component, the multi-year ice. At the same time, the surface temperature in the Arctic is going up, which results in a shorter ice-forming season," Comiso said in a NASA statement. "It would take a persistent cold spell for most multi-year sea ice and other ice types to grow thick enough in the winter to survive the summer melt season and reverse the trend."
Multi-year sea ice hit its record minimum extent in the winter of 2008, when the ice was reduced to about 55 percent of its average extent since the late 1970s, the time when satellite measurements of the ice cap began. The extent of multi-year sea ice then recovered slightly in the three following years, ultimately reaching an extent 34 percent larger than in 2008, the study found. But it dipped again in winter of 2012, to its second lowest extent ever, the researchers report in a recent issue of the Journal of Climate.
The researchers used data collected by NASA's Nimbus-7 satellite and the U.S. Department of Defense's Defense Meteorological Satellite Program to create a time series of multi-year sea ice. The salt content distinguishes the two types of ice: Younger ice, formed from recently frozen ocean water, is saltier than the multi-year type, which loses its salts over time. The level of saltiness changes the ice's electrical properties, causing the ice to different levels of radio waves in the microwave band of the electromagnetic spectrum. The microwave radiometers on the Nimbus-7 satellite pick up these differences.
January 2012 compared to past years
Arctic sea ice extent for January 2012 was the fourth lowest in the satellite record. Including the year 2012, the linear rate of decline for January ice extent over the satellite record is 3.2% per decade.
Based on the satellite record, before 2005 average January ice extent had never been lower than 14 million square kilometers (5.41 million square miles). January ice extent has now fallen below that mark six out of the last seven years.
Monthly January ice extent for 1979 to 2012 shows a decline of 3.2% per decade.
Do what???? Whoever said that our atmosphere would ever resemble Venus's atmosphere? Whoever said that CO2 would be the only cause of our atmosphere ever resembling that of Venus? Should you suggest that I made such claims, then you would be wrong. What I said is that Venus is an example of what happens when an atmosphere runs amok due to greenhouse gases.
Why are there so many posts missing???
Is 30 years of records really any indicator of anything? NASA claims to have Arctic records since 1955. The trouble is the don't say how they acquired any records, because we had no reliable measurements until 1980.
These solve that problem Neapolitan. They are the answer to what you have been saying we need to do.
It's meaningless to compare rate of change over a short-term such as 150 years to a long term such as 5000 years--in general, the shorter period will tend to exhibit more variability potentially. I also seriously doubt that there is any proxy for pH that has a good enough temporal resolution to enable us to rule out any 150-year period of the last 300 million years exhibiting changes that far exceed what we have seen from 1850-2000.
No "breaking" anything here, just an invalid comparison.
Of course, the title does use the word "may", so I guess it really doesn't say anything anyway.
I'm also wondering how many, if any, pH measurements go back 150 years; they're probably mixing proxy data with actual measurements again I guess...
Warmists want it both ways. Just trust them and their manipulated data.
LOL, key words like, maybe, could be, make headlines everyday for all the extrapolated reasons. Ya just wonder who could do that.....?
Mandate :>
Sounds like someone's about to blow a gasket over the ever-increasing stream of real science refuting so-called "global warming." Simple logic contradicts the pseudo-science of AGW.
Really? Can you point us to the non-referenced study from this site you took the text from?
a href="http://www.trust.org/alertnet/news/oceans-acidic-shift-may-be-fastest-in-300-m illion-years/"
You can substantiate what the scientists say with peer reviewed stuff, Can't you ?
Reminds me of the "Black Knight Sketch" LOL
Are you willing to explain the "simple logic" that would contradict AGW?
Neapolitan, I didn't come here to plus or minus comments unfairly. If you'll take just a brief second to look around at your own plussing, and Ms. Colon's plussing, I'm sure you will find that some tend to plus other comments more than some. It's just the natural way of joining with "like" minds if you wish.
I visit these blogs daily to seek weather and climate knowledge, and I've learned a lot, but NONE from you. Can you see my blog activity as an ADMIN? If so, please post it for the world to see.
I'm very glad to see you've used the term "we" so lightly. I take it that means you "speak" for this group, the entire forum, as a matter of fact. Just goes to prove your number of posts carries great value for some, but for me, not so much. I'm not saying you are not knowledgeable about Climate Change; you apparently have great resources available to copy and paste. I do question your knowledge about weather in general, and especially Tropical Weather, and you might be challenged in the upcoming months.
I wish you nothing but the best.
Pretty disingeneous. Of course short term reuslts have greater variability.. in the mathematical truism sense of variability. That is basic statistics. I didn't read the article but in a situation like this you look for causes and system dynamics.
Without a returning force with an acceleration equal to the acceleration of the phenonmena (acceleration in 2nd order sense), the data makes a lot of sense. For example, the sediments can reduce acidity to a certain extent. However the rate of reduction is much less than the contribution from C02 entering into solution. So what mechanism in the past would have handled a similarly enourmous spike in acidity? Maybe a spike from some one-off event could be handled over time but clearly, CO2 is not a one-off event since our rate pf production accelerates.
Your argument is like observing a cold front moving through and then arguing that it is not a change in weather because the measurements made over the last 7 days were only taken every hour and that theoretically it is possible that all the temperatures dipped similarly in one of those hour gaps. Yeah, theoretically you are right: it is mathematically possible, or rather impossible to eliminate that possibility. But what is the mechanism by which the temperature would ahve dipped and then returned? In the case of global warming we have a mechanism that is well studied and well forecast. To say an alternative is theoretically possible without mentioning what it is is just amathematical truism designed to give the denialists some sort of intellectual straw hut to hide inside in order to pretend the wolf doesn't exist.
(Reuters) - Significant declines in perennial Arctic sea ice over the past decade may be intensifying a chemical reaction that leads to deposits of toxic mercury, a NASA-led study showed on Thursday.
The study found that thick, perennial Arctic sea ice was being replaced by a thinner and saltier ice that releases bromine into the air when it interacts with sunlight and cold, said Son Nghiem, a NASA researcher at the Jet Propulsion Laboratory in Pasadena.
That in turn triggers a chemical reaction called a "bromine explosion" that turns gaseous mercury in the atmosphere into a toxic pollutant that falls on snow, land and ice and can accumulate in fish, said Nghiem, lead author of the study.
"Shrinking summer sea ice has drawn much attention to exploiting Arctic resources and improving maritime trading routes," Nghiem said.
"But the change in sea ice composition also has impacts on the environment," he said. "Changing conditions in the Arctic might increase bromine explosions in the future.
Nghiem said the released bromine can also remove ozone from the lowest level of the atmosphere, the troposphere.
Though much of the attention on Arctic sea ice has focused on summer sea ice cover, the NASA-led study, which has been accepted for publication in the Journal of Geophysical Research-Atmospheres, examined perennial sea ice during winter and the transition into spring.
Nghiem said scientists were still trying to determine why the Arctic had lost an estimated one million square kilometers of perennial sea ice over the last 10 years, saying it could be due to a change in wind patterns over that time period.
In March 2008, the extent of year-round perennial sea ice set a 50-year low, shrinking by an area the size of Texas and Arizona combined, according to NASA. It has been replaced by younger, seasonal sea ice that is saltier because it has not undergone the processes that wash out its salts.
The study was conducted by a team from the United States, Canada, Germany and the United Kingdom and combined data from six NASA, European Space Agency and Canadian Space Agency satellites as well as field observations and a model.
Schmallenberg virus affects sheep and cattle, and is probably carried by midges. It was identified in Germany last year, and in the UK in January.
Until 1990, Europe's midge-borne viral diseases were found only in Spain and Portugal; but two have emerged within the last six years in northern Europe.
Experts say the path of Schmallenberg is currently impossible to predict.
Schmallenberg virus - named after the German town where it was first identified - causes fever and diarrhoea in adult animals, but they recover.
However, infection during a critical stage of pregnancy leads to lambs and calves being born with deformation of limbs, spine or brain. Many are stillborn.
Currently it has been found on 83 farms in the UK, mainly in the southeast.
Unpredictable future
The next few months will almost certainly see the birth of more affected lambs and calves resulting from infections their mothers picked up last year, as farms progressively further north go through the calving season.
But after that, it could "burn itself out" or become a regular threat - or anywhere in between, according to leading scientists speaking at a briefing in London.
"There are these two scenarios," said Matthew Baylis from the Institute of Infection and Global Health at Liverpool University.
"The key question is whether the virus will be picked up by the vector (midges) from the calves and lambs that will be born later in the spring, after the midge season starts."
If that happens, he said, more cows and sheep will be infected, with problems emerging next year when they give birth.
But the path is very hard to predict as so little is known about a virus that was only idenfitied a few months ago.
"There is the possibility it will simply die out, but I think that would be too good to be true," said Peter Mertens from the Institute for Animal Health in Surrey.
"There's a lot of virus about, and I think it's quite likely it won't simply go away in one year.
"Is Culicoides (the midge) the only means of spread, or is there something else on a local level - fecal-oral spread, or aerosol (airborne) spread?
"We don't know."
Vaccination needed?
One part of the puzzle that scientists have put together is the influence of climate change on the risks of midge-borne viral diseases.
A higher temperature means an increase in the number of midges, and that they feed more often. It also allows the virus to develop faster.
Using weather and climate models as well as information on the biology of viruses and midges, Prof Baylis's research group showed that recent climatic change in northern Europe has significantly increased the risk of viral midge-borne diseases.
"Temperature changes in Europe which to most of us have felt relatively small have in our model led to a large increase in the risk of viral midge-borne diseases," he said.
The modelling results, he said, reflected what has actually happened across the continent.
"Culicoides infections were first detected in Europe in the 1920s, but only in Spain and Portugal and on the eastern borders, around Turkey," he said.
"Then in 1998 we saw cases in Italy. Bluetongue then emerged in northern Europe in 2006/7, and now we have Schmallenberg."
The modelling suggests other similar diseases should be expected in future, said Prof Mertens, adding: "The doors are open."
Schmallenberg appears to pose no threat to humans, according to monitoring by the Netherlands government health agency.
It appears that currently, little can be done to curb the spread of Schmallenberg if it does emerge as a persistent threat for farmers.
Animals could be sheltered inside during the critical period of their pregancy. Prof Baylis's team has shown this reduces the number of midges, but does not offer complete protection.
Australian farmers, combating a similar virus, have developed regimes whereby female cows that have not previously been infected are made pregnant before the insect season begins.
When they do become infected later in the year, their calves do not suffer, and the cows subsequently become immune.
There is no realistic way to control midge numbers, said Prof Mertens.
Vaccine manufacturers, meanwhile, are working on a vaccine for Schmallenberg, which would take about 18 months to develop.
But given all the things we do not know about the virus, said Prof Mertens, it was not yet proven that vaccination was needed.
As for the rest of your comment, by all means continue to "flag" anything you feel violates community standards, even those that actually don't. But you should know that doing so only hurts your own "karma". And a question: in the interests of fairness, did you indeed "flag" atmo's comment #187?
--Yes, I and others plus some comments more than others, but that's only because some comments are more deserving of plusses than are others. I don't plus spam, I don't plus aimless trolling, I don't plus vile and threatening comments, and, mainly, I don't plus comments that are simple denialist rehashings of the same tired and debunked tropes we've all heard a thousand times. But that's not to say I minus them, or report them. I haven't kept track, but I'd imagine that I've used the minus button no more than 30 times in, say, the last six months, and then only in conjunction with the report button; that's because hitting the minus ensures the comment will stay hidden when I reload the page but before the comment is removed. I do know from long experience that others indiscriminately press the flag and report buttons simply because they disagree with what the commenter wrote, but that's just childish, IMHO. (Also, FWIW, I do on occasion plus particularly poignant comments from those on the other side. I have in the past plussed comments from atmo, and maelstrom, and Oss, and barefoot, and, yes, even you. Keep it above the waist, keep it relevant, keep it honest, and keep it though-provoking, and I may just do that.)
--Yes, I believe Admins can see all blog activity, but not being one myself here, nor ever having been one here, I really have no idea.
Now, what are your own thoughts and feelings on the Venusian heat? Do you believe it's primarily/only from adiabatic processes as atmo claimed? Is it primarily/only from a greenhouse effect as Rookie claimed? Or is it something else (i.e., heat from the planet's core being unable to escape to space) as others have claimed? And as a follow-up: what relevance does it have with what's going on on Earth?
This resulted in a long but very readable text in The New York Review of Books.
Why the Global Warming Skeptics Are Wrong
19 year variability in ocean ph is "virtually indistinguishable"
Contributed by David M. Karl, June 8, 2009 (received for review April 10, 2009)
Old Hat Old news!Not world wide only in North Central Pacific. I love your cherry picking. See this in North Central Pacific NOAA says otherwise:
Y'all with me yet??????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????
Link
Ocean Acidification: The Other Carbon Dioxide Problem
Fundamental changes in seawater chemistry are occurring throughout the world's oceans. Since the beginning of the industrial revolution, the release of carbon dioxide (CO2) from humankind's industrial and agricultural activities has increased the amount of CO2 in the atmosphere. The ocean absorbs about a quarter of the CO2 we release into the atmosphere every year, so as atmospheric CO2 levels increase, so do the levels in the ocean. Initially, many scientists focused on the benefits of the ocean removing this greenhouse gas from the atmosphere. However, decades of ocean observations now show that there is also a downside %u2014 the CO2 absorbed by the ocean is changing the chemistry of the seawater, a process called OCEAN ACIDIFICATION.
Mission statement
To understand the changing chemistry of the oceans and the impacts of ocean acidification on marine ecosystems. Our observations of key physical, chemical, and biological parameters support NOAA's overall efforts to predict how marine ecosystems will respond and to develop management strategies for adapting to the consequences of ocean acidification.
Oceanographers in our group have been studying how CO2 emissions affect the ocean system for more than three decades and continue to monitor ocean acidification in all the world%u2019s oceans from coral reef ecosystems to deep North Pacific waters. Our group collects several types of carbon measurements throughout the world%u2019s oceans. We participate in large-scale research cruises across ocean basins and along coastlines at regular intervals to study how ocean chemistry is changing through time.
We also make measurements of the partial pressure of CO2 (pCO2) in the surface water of the world%u2019s oceans using automated analytical systems on moorings and underway platforms. We are currently in the process of adding pH, oxygen, chlorophyll, and turbidity sensors to our existing moored and underway systems to more accurately and precisely study the changes associated with ocean acidification.
These prevents the above:
Y'all with me yet??????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????
Ah, yes. The Black Knight. How appropriate that you would choose this video. No matter what is happening, no matter all of the evidence presented before him, the Black Knight simply denies that anything has happened at all. He will, at best, admit that it is just a minor problem and that nothing should be made of it. I believe that you have very well explained the problem, with your little video. Those that would deny what is obviously taking place. Thank you, for making this point so obvious to anyone that is paying attention.
Did you read the very first sentence of the abstract?
"Atmospheric carbon dioxide (CO2) is increasing at an accelerating rate, primarily due to fossil fuel combustion and land use change."
Perhaps the second sentence is also noteworthy?
"A substantial fraction of anthropogenic CO2 emissions is absorbed by the oceans, resulting in a reduction of seawater pH."
Are we to ignore the third sentence of the abstract?
"Continued acidification may over time have profound effects on marine biota and biogeochemical cycles."
The rest of the abstract does, indeed, discuss the short duration of actual measurements and the accounting for other possible factors concerning the acidification. What it does not do is dismiss the obvious. The obvious is the first three sentences of the abstract.
I am beginning to see that those that would deny the AGWT are starting to do so with articles that actually show support for the AGWT. This is simply because the validity of the AGWT is becoming very apparent to all that have even a basic understanding of the science. Those that still deny the science are merely questioning what? I am not sure. It is going to happen, but when is an uncertainty? It is going to happen, but is it going to be that bad? It is going to happen, but natural cycles have already happened before? ( To this I would say, our activities of burning fossil fuels are not part of the natural cycles. ) Take a close look at all of the physical observations from around the world and you will have good answers to these questions. Unless, of course, you think that ancient aliens left a huge canister of CO2 laying around that was set to release its contents about now. Even if this were true, it does not omit what we are doing ourselves.
Maybe...The Nobel Foundation's criteria for awards aren't exactly that impressive anymore; perhaps a low budget indie film portraying my point would suffice.
Seriously though, isn't it common sense that variation over a 150-year time period would naturally be greater than that of a longer time period of 5000 years. Do you not see the point that I was making?
The data is the supporting evidence of the hypothesis that "X is making/did make the ocean more acidic". If the data comparison is inappropriate it cannot support the hypothesis very well, even if it "makes sense". That would be overlooking the problems with the comparison simply because it validates the answer you were looking for, something that seems to occur quite often in this field.
The idea that the recent 150-year change is an "enormous spike" is assuming that over no similar period in the past (150-year period or similar) exhibited a similar "spike". Showing that it didn't over a 5000 year period does not show that at all. It is certainly possible that there were shorter time periods within that the 5000-year one where changes were greater than the recent changes, until temporally precise data can be found to show otherwise.
The "cold front" argument isn't valid here, in my opinion. You can certainly measure temperatures
accurateprecisely enough to determine if a cold front has passed. Using the "cold front" analogy to the original acidification argument, it would be like as if you could only measure temperatures as a week average because of temporal precision limitations, and you tried to argue that a cold front did not pass because two weeks exhibited the same overall average temperature.The average proxy-derived pH change value (even assuming that proxy is good enough, which we're glossing over for this argument) is not precise enough to state that recent 150-year pH change is unmatched, unless specific shorter time periods on the scale of 150 years can be measured for comparison.
This is way I see it, at least--especially given the scope of the original claim. Fastest shift in 300 million years? Seriously? I bet we can't even get a good 100,000 year average for global ocean pH that far back. How many proxy points would that be based on geographically I wonder?
Edited
It is called cherry picking information to support your cause!
The point of my post was that your conclusion in bold is not a valid statistical statement. It's like kriging when searching for gold: there is no way that a set of data samples from boreholes can eliminate the possibility of a gold bearing vein, but in the absence of a changing geological structure the statistical treatment is assumed to be valid.
In the case of CO2, you state that are possible gaps in the data but don't provide an evidence/hypothesis about a physical structure, you only state that it could be true, essentially it is a deus ex-machina hypothesis. On the other hand, it is easy to demonstrate that dissolving CO2 into seawater does raise its acidity (lower its ph).
Ah yes, how appropriate it is when one shows how ideologically based perception can be confining eh?
How is that ID doing? .
The others parts are obvious to all that pay attention :)
I hope you don't mind if I pray for you......
Sigh...
Should it be true that our burning of fossil fuels began in earnest some 5,000 years ago, then it would be common sense to look at the data for more than just 150 years or for any shorter period. We should look at the data over the past 5,000 years to see what impact the burning of fossil fuels has had on the global climate, if we had starting burning fossil fuels then. Common sense should also dictate that we look at the data over the past 150 years, the beginning of our burning of fossil fuels, as opposed to just any 10 years of data from these 150 years.
What are we really trying to ascertain here? Is it not to see what impact the burning of fossil fuels has had on our global climate? Let us say that we had complete data of our global climate and a full understanding of this data for the past 1,000,000,000 years. Should we try to incorporate this data into our attempt to ascertain the impact of our burning of fossil fuels when have only been doing so for 150 years? Should we do so, then we must filter out all of the forcing for a global climate change that occurred over that 1,000,000,000 year period. What purpose would this serve? Certainly we would benefit from knowing all of the forcing that had impacted our global climate before. This information should only be used as points of reference and not as a determination of what is happening with our global climate today. This is true, unless the past events are also events that are occurring today and at a rate as to have caused the past global climate changes.
Since what we are really trying to ascertain is how much our burning of fossil fuels has impacted our global climate, then we should only be concerned with the time period just prior to our doing so. We have been burning fossil fuels for about 150 years. We should then look back to see what the climate was 150 years prior to our burning of fossil fuels. This would give a good starting point to see how our burning of fossil fuels has impacted our climate. Looking at time periods before this would be just so much noise. Unless these is something from before this time period that is effecting our global climate now, it has no real relevance on any global climate change we are witnessing now.
Let us employ a little more common sense. We know that CO2 is a greenhouse gas. We know that greenhouse gases, in sufficient quantities, will cause a warming of our global climate. We know that our burning of fossil fuels releases tons per day of CO2 into our atmosphere. We know that a warming global climate will begin to trigger other processes, such as the releasing of previously frozen methane into our atmosphere. We know that methane is an even more potent greenhouse gas than is CO2. We know that a warming global climate will lead to ice loss. We know that ice loss will cause the loss of reflective surfaces with dark and more heat absorbing surfaces. Use your common sense and see if you are able to explain to me how our burning of fossil fuels will not have an appreciable impact on the warming of our global climate?
Yes, I know. There will be some that will miss the point of what I am making here.
Hello, Ossqss. How have you been doing?
You do realize that your entire post could be turned right back to you, are you not? Including the MC Hammer music video.
--The previous single-day record for March tornadoes was 59. The SPC is reporting 94 as of now. Even if there are no more reported, and even if, say, 30% of those reported are later rejected, today will easily be the most tornadic day ever recorded in March. And it came, of course, two whole days after a previous outbreak.
--As some have noted, the Earth's oceans may very well be acidifying at the fastest rate in 300,000,000 years. Three. Hundred. Million. Years. It's acidifying so fast, in fact, that our ability to feed ourselves is going to be greatly imperiled.
I just wanted to list those few coincidences. I wouldn't worry about them, or even give them a second thought. I'm sure it's all part of a natural cycle...
Today is Friday, the 2. March 2012
The 13th Baktun begins at Friday, the 21. December 2012
294 days remaining!
1871706 days counted since the zero-date (11th August 3114 B.C., gregorian calendar)
The actual date in the mayan Longcount and the Tzolkin/Haab-Calendar:
12
Baktun
19
Katun
19
Tun
3
Uinal
6
Kin
9
Cimi
14
Kayab
These prevent all of that above Neapolitan:
A very honest reply, and thank you for it. Actually, I'm not sure where I stand on the Venus issue, nor the entire Global Warming, or lack of, or increase of said subject. I do respect Atmoaggie and hold him in the highest regard as he a very intelligent person with the education to back it up. I pretty much respect everyone here, or try to. Good info to be found, if you know where, and who to seek it from. I'm not a denialist, nor am I on the other side of the fence; I guess you can say I ride the middle of it. My biggest problem is when I joined Master's blog, it was Tropical Weather, and Severe weather, during the "off season." Since then, Master's has changed the blog to offer more of his own opinions on AGW. And, that is his opinion. You just shouldn't change in the middle of the stream. I realize you are a newbie here, relatively speaking. You cannot recall when the site was not full of the AGW talk because you weren't here, or either you weren't posting. I do think, however, you grabbed the AGW talk by the horns, and ran with it, and added to the comments. You didn't help the situation much. (Or, maybe you did, in Master's opinion.) It's not about AGW that was presented to me a long time ago, it was about tropical, and severe weather. People were posting maps and charts ALL over the place, even in the off season. Now, not so much. I don't come here to cause problems; I'm NOT a troll, and I would hope that you could see that. I don't have your post numbers, but I've got you beat by a long shot by my membership date.
To me, it was more important today to watch the radar... and the cape values... and the surface maps.... as we watched so many people die over the tri state area. Watching the radar as so many people lost their homes.... their lives... and everything. It was really horrible, and the real damage will dawn with the morning hours.
If you have anything to teach to anyone, please let me know. I don't require your AGW lectures, and sometimes you take the tone that tells me "I am better than you and everyone else".... and you might not mean to do that, but that's the tone I take from you. But if you have ANYTHING at all to offer to someone regarding Tropical Systems, and severe weather, I'm certainly open to your suggestions.
December 21 is my birthday. Nothing special ever happens on my birthday. I don't expect anything different this time.
Link
Bromine explosion on March 13, 2008 across the western Northwest Territories in Canada looking toward the Mackenzie Mountains at the horizon, which prevented the bromine from crossing over into Alaska. Image credit: NASA/JPL-Caltech/University of Bremen
NASA Finds Sea Ice Driving Arctic Air Pollutants
PASADENA, Calif. – Drastic reductions in Arctic sea ice in the last decade may be intensifying the chemical release of bromine into the atmosphere, resulting in ground-level ozone depletion and the deposit of toxic mercury in the Arctic, according to a new NASA-led study.
The connection between changes in the Arctic Ocean's ice cover and bromine chemical processes is determined by the interaction between the salt in sea ice, frigid temperatures and sunlight. When these mix, the salty ice releases bromine into the air and starts a cascade of chemical reactions called a "bromine explosion." These reactions rapidly create more molecules of bromine monoxide in the atmosphere. Bromine then reacts with a gaseous form of mercury, turning it into a pollutant that falls to Earth's surface.
Bromine also can remove ozone from the lowest layer of the atmosphere, the troposphere. Despite ozone's beneficial role blocking harmful radiation in the stratosphere, ozone is a pollutant in the ground-level troposphere.
A team from the United States, Canada, Germany, and the United Kingdom, led by Son Nghiem of NASA's Jet Propulsion Laboratory in Pasadena, Calif., produced the study, which has been accepted for publication in the Journal of Geophysical Research- Atmospheres. The team combined data from six NASA, European Space Agency and Canadian Space Agency satellites; field observations and a model of how air moves in the atmosphere to link Arctic sea ice changes to bromine explosions over the Beaufort Sea, extending to the Amundsen Gulf in the Canadian Arctic.
"Shrinking summer sea ice has drawn much attention to exploiting Arctic resources and improving maritime trading routes," Nghiem said. "But the change in sea ice composition also has impacts on the environment. Changing conditions in the Arctic might increase bromine explosions in the future."
The study was undertaken to better understand the fundamental nature of bromine explosions, which first were observed in the Canadian Arctic more than two decades ago. The team of scientists wanted to find if the explosions occur in the troposphere or higher in the stratosphere.
Nghiem's team used the topography of mountain ranges in Alaska and Canada as a "ruler" to measure the altitude at which the explosions took place. In the spring of 2008, satellites detected increased concentrations of bromine, which were associated with a decrease of gaseous mercury and ozone. After the researchers verified the satellite observations with field measurements, they used an atmospheric model to study how the wind transported the bromine plumes across the Arctic.
The model, together with satellite observations, showed the Alaskan Brooks Range and the Canadian Richardson and Mackenzie mountains stopped bromine from moving into Alaska's interior. Since most of these mountains are lower than 6,560 feet (2,000 meters), the researchers determined the bromine explosion was confined to the lower troposphere.
"If the bromine explosion had been in the stratosphere, 5 miles [8 kilometers] or higher above the ground, the mountains would not have been able to stop it and the bromine would have been transported inland," Nghiem said.
After the researchers found that bromine explosions occur in the lowest level of the atmosphere, they could relate their origin to sources on the surface. Their model, tracing air rising from the salty ice, tied the bromine releases to recent changes in Arctic sea ice that have led to a much saltier sea ice surface.
In March 2008, the extent of year-round perennial sea ice eclipsed the 50-year record low set in March 2007, shrinking by 386,100 square miles (one million square kilometers) -- an area the size of Texas and Arizona combined. Seasonal ice, which forms over the winter when seawater freezes, now occupies the space of the lost perennial ice. This younger ice is much saltier than its older counterpart because it has not had time to undergo processes that drain its sea salts. It also contains more frost flowers -- clumps of ice crystals up to four times saltier than ocean waters -- providing more salt sources to fuel bromine releases.
Nghiem said if sea ice continues to be dominated by younger saltier ice, and Arctic extreme cold spells occur more often, bromine explosions are likely to increase in the future.
Nghiem is leading an Arctic field campaign this month that will provide new insights into bromine explosions and their impacts. NASA's Bromine, Ozone, and Mercury Experiment (BROMEX) involves international contributions by more than 20 organizations. The new studies will complement those of a previously conducted NASA field campaign, Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), which is providing scientists with valuable data for studies of bromine.
This study was funded by NASA, the National Oceanic and Atmospheric Administration, the National Science Foundation, the Office of Naval Research, the International Polar Year Program, Environment Canada, the Natural Sciences and Engineering Council of Canada, the European Space Agency, the State of Bremen, the German Aerospace Center, and the European Organisation for the Exploitation of Meteorological Satellites.
For more information about NASA programs, visit: http://www.nasa.gov .
JPL is managed for NASA by the California Institute of Technology in Pasadena.
Last month the extent of sea ice covering the Arctic Ocean declined to the second-lowest extent on record. Satellite data from NASA and the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado in Boulder showed that the summertime sea ice cover narrowly avoided a new record low.
NASA satellite data reveals how this year's minimum sea ice extent, reached on Sept. 9 as depicted here, declined to a level far smaller than the 30-year average (in yellow) and opened up Northwest Passage shipping lanes (in red). (Credit: NASA Goddard's Scientific Visualization Studio)
The Arctic ice cap grows each winter as the sun sets for several months and shrinks each summer as the sun rises higher in the northern sky. Each year the Arctic sea ice reaches its annual minimum extent in September. It hit a record low in 2007.
The near-record ice-melt followed higher-than-average summer temperatures, but without the unusual weather conditions that contributed to the extreme melt of 2007. "Atmospheric and oceanic conditions were not as conducive to ice loss this year, but the melt still neared 2007 levels," said NSIDC scientist Walt Meier. "This probably reflects loss of multiyear ice in the Beaufort and Chukchi seas as well as other factors that are making the ice more vulnerable."
Joey Comiso, senior scientist at NASA's Goddard Space Flight Center in Greenbelt, Md., said the continued low minimum sea ice levels fits into the large-scale decline pattern that scientists have watched unfold over the past three decades.
"The sea ice is not only declining, the pace of the decline is becoming more drastic," Comiso said. "The older, thicker ice is declining faster than the rest, making for a more vulnerable perennial ice cover."
While the sea ice extent did not dip below the 2007 record, the sea ice area as measured by the microwave radiometer on NASA's Aqua satellite did drop slightly lower than 2007 levels for about 10 days in early September, Comiso said. Sea ice "area" differs from extent in that it equals the actual surface area covered by ice, while extent includes any area where ice covers at least 15 percent of the ocean.
Arctic sea ice extent on Sept. 9, the lowest point this year, was 4.33 million square kilometers (1.67 million square miles). Averaged over the month of September, ice extent was 4.61 million square kilometers (1.78 million square miles). This places 2011 as the second lowest ice extent both for the daily minimum extent and the monthly average. Ice extent was 2.43 million square kilometers (938,000 square miles) below the 1979 to 2000 average.
This summer's low ice extent continued the downward trend seen over the last 30 years, which scientists attribute largely to warming temperatures caused by climate change. Data show that Arctic sea ice has been declining both in extent and thickness. Since 1979, September Arctic sea ice extent has declined by 12 percent per decade.
"The oldest and thickest ice in the Arctic continues to decline, especially in the Beaufort Sea and the Canada Basin," NSIDC scientist Julienne Stroeve said. "This appears to be an important driver for the low sea ice conditions over the past few summers."
Climate models have suggested that the Arctic could lose almost all of its summer ice cover by 2100, but in recent years, ice extent has declined faster than the models predicted.
NASA monitors and studies changing sea ice conditions in both the Arctic and Antarctic with a variety of spaceborne and airborne research capabilities. This month NASA resumes Operation IceBridge, a multi-year series of flights over sea ice and ice sheets at both poles. This fall's campaign will be based out of Punta Arenas, Chile, and make flights over Antarctica. NASA also continues work toward launching ICESat-2 in 2016, which will continue its predecessor's crucial laser altimetry observations of ice cover from space.
Patrick Lynch
NASA's Earth Science News Team
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