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Excellent, unless you are one of thousands of species that have evolved for specific climates and environmental conditions that are being adversely affected by AGW. Unless you are a member of a coral community utterly dependent on constant water chemistry and find yourself awash in a human-induced acidic ocean and nitrate pollution. Unless you are an eskimo and family whose livelihood is dependent on the Arctic ice, which seems destined to melt away by about 2050 and take with it its teeming aquatic life. Unless you are one of millions of people who already live a tenuous existence on marginal land that will become utterly desolate when the desert encroaches. Unless you are one of the billions who live at or near sea level. If you are not one of those, yeah, things might be peachy. But then, you will have identified yourself as a weed. But I doubt even the weeds will make it through unscathed.
Funny how no animals have been shown to be negatively impacted by the warming from the LIA. In fact contrary to the hysterical hyperbole from the warmist fraudsters the polar bear population has increased by 2500-5000 since 2001 which is the opposite of the claims made by you and your fellow socks.
Probably because there was no one conducting a population census of species at the end of the little ice age.
But the LIA had a severe impact on people:
The Little Ice Age in Europe - Influence of Dramatic Climate Shifts on European Civilizations: The Rise and Fall of the Vikings and the Little Ice Age
You shouldn't listen to the fossil fuel shills at Heartland dude.
CDC - Extreme Heat and Your Health
Yeah --- it was a rhetorical... Well if ya DO KNOW where on that chart we are --- we've not yet come CLOSE to an interglacial peak have we? As they say on Wall Street
"past performance is no indication of future valuations" ---- BUT ---- I'd suggest we have a ways to go before we panic and say we're screwing up the recovery from the last Ice Age.. That is --- if Milankovitch cycles really matter...
BTW:: Have you ever heard of the Center of Mass of Solar System (CMSS) theory? Haven't had the instruments in space LONG ENOUGH to even measure the DOZENS of possible modulations of solar output.. Both in intensity and maybe MORE importantly, spectral content..
In fact, for at least the last 8,000 years leading up to 1850, we were in a climate downturn wrt temperature. The last 150 years has seen that downturn reverse itself at a faster rate than anything seen in the last 11,000 years. The only explanation for this is the billions of tons of GHGs we are pumping into the atmosphere, something you don't see in any of the data for the previous 11,000 years.
Except for the Holocene Thermal Maximum, and the Roman Warming Period and the Medieval Warming Period. Other than that I would agree with you. Funny how you try and excise them from the historical record. You revisionists seem to do that a lot.
Funny how no animals have been shown to be negatively impacted by the warming from the LIA. In fact contrary to the hysterical hyperbole from the warmist fraudsters the polar bear population has increased by 2500-5000 since 2001 which is the opposite of the claims made by you and your fellow socks.
Probably because there was no one conducting a population census of species at the end of the little ice age.
But the LIA had a severe impact on people:
The Little Ice Age in Europe - Influence of Dramatic Climate Shifts on European Civilizations: The Rise and Fall of the Vikings and the Little Ice Age
Yes, the LIA had a severe impact. Ice Ages suck.
Why do they call warm periods Climactic Optimums?
In fact, for at least the last 8,000 years leading up to 1850, we were in a climate downturn wrt temperature. The last 150 years has seen that downturn reverse itself at a faster rate than anything seen in the last 11,000 years. The only explanation for this is the billions of tons of GHGs we are pumping into the atmosphere, something you don't see in any of the data for the previous 11,000 years.
Except for the Holocene Thermal Maximum, and the Roman Warming Period and the Medieval Warming Period. Other than that I would agree with you. Funny how you try and excise them from the historical record. You revisionists seem to do that a lot.
I've done no such thing. Funny how you pull stupid accusations out of your arse when confronted with facts you can't ignore. Yes, those events occurred. Compared to the 8,000 years trend of cooling, they are but blips, significant blips, but blips nonetheless.
In fact, for at least the last 8,000 years leading up to 1850, we were in a climate downturn wrt temperature. The last 150 years has seen that downturn reverse itself at a faster rate than anything seen in the last 11,000 years.
Excellent! Downturns in temperature are bad. Ice Ages suck.
Excellent, unless you are one of thousands of species that have evolved for specific climates and environmental conditions that are being adversely affected by AGW. Unless you are a member of a coral community utterly dependent on constant water chemistry and find yourself awash in a human-induced acidic ocean and nitrate pollution. Unless you are an eskimo and family whose livelihood is dependent on the Arctic ice, which seems destined to melt away by about 2050 and take with it its teeming aquatic life. Unless you are one of millions of people who already live a tenuous existence on marginal land that will become utterly desolate when the desert encroaches. Unless you are one of the billions who live at or near sea level. If you are not one of those, yeah, things might be peachy. But then, you will have identified yourself as a weed. But I doubt even the weeds will make it through unscathed.
Show me a specie that can't cope with 0.15degC/decade and I'll show a specie that has OTHER major issues.. You may include homo sapien in the list if you truly want to...
Excellent, unless you are one of thousands of species that have evolved for specific climates and environmental conditions that are being adversely affected by AGW. Unless you are a member of a coral community utterly dependent on constant water chemistry and find yourself awash in a human-induced acidic ocean and nitrate pollution. Unless you are an eskimo and family whose livelihood is dependent on the Arctic ice, which seems destined to melt away by about 2050 and take with it its teeming aquatic life. Unless you are one of millions of people who already live a tenuous existence on marginal land that will become utterly desolate when the desert encroaches. Unless you are one of the billions who live at or near sea level. If you are not one of those, yeah, things might be peachy. But then, you will have identified yourself as a weed. But I doubt even the weeds will make it through unscathed.
Show me a specie that can't cope with 0.15degC/decade and I'll show a specie that has OTHER major issues.. You may include homo sapien in the list if you truly want to...
If that were how it works, you'd have a point. Guess what? That's not how it works. Species live in regional climates, and are affected most severely by regional changes. In the Arctic, global warming is having its most profound effects. The changes are severe, and are stressing many species. In the western U.S. we are seeing a severe long-term drought become ever more catastrophic as the air dries and temperatures rise. What kind of effect do you believe these regional changes are having on species? Do you honestly think they are taking it in their stride? In the Siberian Sea, warming sea water is releasing huge quantities of methane (a more potent GHG than CO2) which is not only being released into the atmosphere, but into the sea itself, setting the stage for a massive die off of species as the sea becomes anoxic. When the bulk of the methane stored in the Arctic permafrost is released in the coming decades, what do you think will be the net effect of that event?
More hyperbole I see. When did that methane start getting released?
Probably because there was no one conducting a population census of species at the end of the little ice age.
But the LIA had a severe impact on people:
The Little Ice Age in Europe - Influence of Dramatic Climate Shifts on European Civilizations: The Rise and Fall of the Vikings and the Little Ice Age
Yes, the LIA had a severe impact. Ice Ages suck.
Why do they call warm periods Climactic Optimums?
You can call them interglacials like everyone else does.
Excellent, unless you are one of thousands of species that have evolved for specific climates and environmental conditions that are being adversely affected by AGW. Unless you are a member of a coral community utterly dependent on constant water chemistry and find yourself awash in a human-induced acidic ocean and nitrate pollution. Unless you are an eskimo and family whose livelihood is dependent on the Arctic ice, which seems destined to melt away by about 2050 and take with it its teeming aquatic life. Unless you are one of millions of people who already live a tenuous existence on marginal land that will become utterly desolate when the desert encroaches. Unless you are one of the billions who live at or near sea level. If you are not one of those, yeah, things might be peachy. But then, you will have identified yourself as a weed. But I doubt even the weeds will make it through unscathed.
Show me a specie that can't cope with 0.15degC/decade and I'll show a specie that has OTHER major issues.. You may include homo sapien in the list if you truly want to...
If that were how it works, you'd have a point. Guess what? That's not how it works. Species live in regional climates, and are affected most severely by regional changes. In the Arctic, global warming is having its most profound effects. The changes are severe, and are stressing many species. In the western U.S. we are seeing a severe long-term drought become ever more catastrophic as the air dries and temperatures rise. What kind of effect do you believe these regional changes are having on species? Do you honestly think they are taking it in their stride? In the Siberian Sea, warming sea water is releasing huge quantities of methane (a more potent GHG than CO2) which is not only being released into the atmosphere, but into the sea itself, setting the stage for a massive die off of species as the sea becomes anoxic. When the bulk of the methane stored in the Arctic permafrost is released in the coming decades, what do you think will be the net effect of that event?
Supersaturated Siberian Seas | Methanenet
Covered in ice for 265 days of the year, and bordered by the frozen
wastes of the Siberian tundra, it is hardly surprising that the shallow
seas of East Siberian Arctic Shelf (ESAS) have not before now been
subject to extensive monitoring for methane emissions. However, due to
the efforts of an international collaboration between researchers based
in Alaska, Vladivostock and Stockholm, a comprehensive survey of methane
concentrations in these waters has now been conducted. The results,
reported in Science (Shakhova et al. 2010) make compelling reading and
raise new questions about future Arctic methane fluxes.
----------
Based on all the observations, the team calculated annual atmospheric
methane flux from the ESAS at 7.98 Tg C-CH4. To put this in context,
previous research has estimated the global methane flux from oceans as 4
– 15 Tg C-CH4 y-1 (IPCC, 2007).
The influence of termites on atmospheric trace gases: CH4, CO2, CHCl3, N2O, CO,
The influence of termites on atmospheric trace gases: CH4, CO2, CHCl3,
N2O, CO, H2, and light hydrocarbons
Khalil, M. A. K.; Rasmussen, R. A.; French, J. R. J.; Holt, J. A.
Journal of Geophysical Research, Volume 95, Issue D4, p. 3619-3634
Based on field studies of mounds of Australian termites we estimate that on a global scale termites emit about 12 × 1012 g/yr of methane (< 20 tg/yr) and about 4 ×1015 g CO2/yr (< 8 pg/yr). Most of the detailed results are based on studies of the species Coptotermes lacteus. We found that in mid-latitudes the emissions vary seasonally. .
Show me a specie that can't cope with 0.15degC/decade and I'll show a specie that has OTHER major issues.. You may include homo sapien in the list if you truly want to...
If that were how it works, you'd have a point. Guess what? That's not how it works. Species live in regional climates, and are affected most severely by regional changes. In the Arctic, global warming is having its most profound effects. The changes are severe, and are stressing many species. In the western U.S. we are seeing a severe long-term drought become ever more catastrophic as the air dries and temperatures rise. What kind of effect do you believe these regional changes are having on species? Do you honestly think they are taking it in their stride? In the Siberian Sea, warming sea water is releasing huge quantities of methane (a more potent GHG than CO2) which is not only being released into the atmosphere, but into the sea itself, setting the stage for a massive die off of species as the sea becomes anoxic. When the bulk of the methane stored in the Arctic permafrost is released in the coming decades, what do you think will be the net effect of that event?
First they were gonna die because of 0.15degC/decade.. Now if THAT doesn't kill 'em, you've damned them with droughts and floods and the other plagues. If that STILL don't work --- bring on the toxic gases.. Goalposts are moving here. I'll pass on the plagues right now -- because you're Siberian Methane story is quite scary...
Seems we know absolutely JUNK about the historical levels of methane in the frozen Siberian shelf..
Show me a specie that can't cope with 0.15degC/decade and I'll show a specie that has OTHER major issues.. You may include homo sapien in the list if you truly want to...
If that were how it works, you'd have a point. Guess what? That's not how it works. Species live in regional climates, and are affected most severely by regional changes. In the Arctic, global warming is having its most profound effects. The changes are severe, and are stressing many species. In the western U.S. we are seeing a severe long-term drought become ever more catastrophic as the air dries and temperatures rise. What kind of effect do you believe these regional changes are having on species? Do you honestly think they are taking it in their stride? In the Siberian Sea, warming sea water is releasing huge quantities of methane (a more potent GHG than CO2) which is not only being released into the atmosphere, but into the sea itself, setting the stage for a massive die off of species as the sea becomes anoxic. When the bulk of the methane stored in the Arctic permafrost is released in the coming decades, what do you think will be the net effect of that event?
This is not a trick question.....
Don't stress Thunder. If it's real it won't matter. You'll be long since dead.
If that were how it works, you'd have a point. Guess what? That's not how it works. Species live in regional climates, and are affected most severely by regional changes. In the Arctic, global warming is having its most profound effects. The changes are severe, and are stressing many species. In the western U.S. we are seeing a severe long-term drought become ever more catastrophic as the air dries and temperatures rise. What kind of effect do you believe these regional changes are having on species? Do you honestly think they are taking it in their stride? In the Siberian Sea, warming sea water is releasing huge quantities of methane (a more potent GHG than CO2) which is not only being released into the atmosphere, but into the sea itself, setting the stage for a massive die off of species as the sea becomes anoxic. When the bulk of the methane stored in the Arctic permafrost is released in the coming decades, what do you think will be the net effect of that event?
First they were gonna die because of 0.15degC/decade.. Now if THAT doesn't kill 'em, you've damned them with droughts and floods and the other plagues. If that STILL don't work --- bring on the toxic gases.. Goalposts are moving here. I'll pass on the plagues right now -- because you're Siberian Methane story is quite scary...
Ever hear of positive feedback loops?
Seems we know absolutely JUNK about the historical levels of methane in the frozen Siberian shelf..
1.^ Bloom, A. A.; Palmer, P. I.; Fraser, A.; Reay, D. S.; Frankenberg, C. (2010). "Large-Scale Controls of Methanogenesis Inferred from Methane and Gravity Spaceborne Data". Science 327 (5963): 322325. Bibcode:2010Sci...327..322B. doi:10.1126/science.1175176. PMID 20075250. edit
2.^ Walter, K. M.; Chanton, J. P.; Chapin, F. S.; Schuur, E. A. G.; Zimov, S. A. (2008). "Methane production and bubble emissions from arctic lakes: Isotopic implications for source pathways and ages". Journal of Geophysical Research 113: G00A08. Bibcode:2008JGRG..11300A08W. doi:10.1029/2007JG000569. edit
3.^ a b Zimov, Sa; Schuur, Ea; Chapin, Fs, 3Rd (Jun 2006). "Climate change. Permafrost and the global carbon budget.". Science 312 (5780): 16123. doi:10.1126/science.1128908. ISSN 0036-8075. PMID 16778046.
4.^ a b c Shakhova, Natalia (2005). "The distribution of methane on the Siberian Arctic shelves: Implications for the marine methane cycle". Geophysical Research Letters 32 (9): L09601. Bibcode:2005GeoRL..3209601S. doi:10.1029/2005GL022751.
5.^ a b c Shakhova, Natalia; Semiletov, Igor (2007). "Methane release and coastal environment in the East Siberian Arctic shelf". Journal of Marine Systems 66 (14): 227243. Bibcode:2007JMS....66..227S. doi:10.1016/j.jmarsys.2006.06.006
6.^ Climate Change 2001: The Scientific Basis (Cambridge Univ. Press, Cambridge, 2001)
7.^ N. E. Shakhova, I. P. Semiletov, A. N. Salyuk, N. N. Belcheva, and D. A. Kosmach, (2007). "Methane Anomalies in the Near-Water Atmospheric Layer above the Shelf of East Siberian Arctic Shelf". Doklady Earth Sciences 415 (5): 764768. Bibcode:2007DokES.415..764S. doi:10.1134/S1028334X07050236.
8.^ Torn, M.; Chapiniii, F. (1993). "Environmental and biotic controls over methane flux from Arctic tundra". Chemosphere 26: 357. doi:10.1016/0045-6535(93)90431-4. edit
9.^ Whalen, S. C.; Reeburgh, W. S. (1990). "Consumption of atmospheric methane by tundra soils". Nature 346 (6280): 160. Bibcode:1990Natur.346..160W. doi:10.1038/346160a0. edit
10.^ Kerr, R. A. (2010). "'Arctic Armageddon' Needs More Science, Less Hype". Science 329 (5992): 620621. doi:10.1126/science.329.5992.620. PMID 20688993. edit: Transcript of related podcast "Science Podcast". Science 329 (5992): 697691. 2010. doi:10.1126/science.329.5992.697-b. edit
11.^ Walter, Km; Zimov, Sa; Chanton, Jp; Verbyla, D; Chapin, Fs, 3Rd (Sep 2006). "Methane bubbling from Siberian thaw lakes as a positive feedback to climate warming". Nature 443 (7107): 715. Bibcode:2006Natur.443...71W. doi:10.1038/nature05040. ISSN 0028-0836. PMID 16957728.
12.^ Shakhova N., Semiletov I., Salyuk A., Kosmach D., Bel'cheva N. (2007). "Methane release on the Arctic East Siberian shelf". Geophysical Research Abstracts 9: 01071.
13.^ N. Shakhova, I. Semiletov, A. Salyuk, D. Kosmach (2008), Anomalies of methane in the atmosphere over the East Siberian shelf: Is there any sign of methane leakage from shallow shelf hydrates?, EGU General Assembly 2008, Geophysical Research Abstracts, 10, EGU2008-A-01526
14.^ IMPACTS: On the Threshold of Abrupt Climate Changes, Lawrence Berkeley National Laboratory News Center, 17 September 2008
15.^ CCSP, 2008: Abrupt Climate Change. A report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research (Clark, P.U., A.J. Weaver (coordinating lead authors), E. Brook, E.R. Cook, T.L. Delworth, and K. Steffen (chapter lead authors)). U.S. Geological Survey, Reston, VA, 459 pp.
16.^ Susan Q. Stranahan (30 Oct 2008). "Melting Arctic Ocean Raises Threat of 'Methane Time Bomb'". Yale Environment 360. Yale School of Forestry and Environmental Studies. Retrieved 14 May 2009.
17.^ a b c d "Permafrost Threatened by Rapid Retreat of Arctic Sea Ice, NCAR Study Finds". University Corporation for Atmospheric Research. 2008-06-10. Retrieved 2008-06-11.
18.^ Lawrence, David M.; Slater, Andrew G.; Tomas, Robert A.; Holland, Marika M.; Deser, Clara (2008). "Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss". Geophysical Research Letters 35 (11): L11506. Bibcode:2008GeoRL..3511506L. doi:10.1029/2008GL033985
19.^ Mason Inman (19 December 2008). "Methane Bubbling Up From Undersea Permafrost?". National Geographic News. Retrieved 14 May 2009.
20.^ Pearce, Fred (28 March 09). "arctic-meltdown-is-a-threat-to-humanity". newscientist. Reed Business Information. Archived from the original on 29 March 2009. Retrieved 2009-03-29.
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23.^ a b Vast methane 'plumes' seen in Arctic ocean as sea ice retreats Tuesday 13 December 2011 Vast methane 'plumes' seen in Arctic ocean as sea ice retreats - Science - News - The Independent
24.^ As Arctic Ocean warms, megatonnes of methane bubble up - environment - 17 August 2009 - New Scientist
25.^ Is Global Warming Happening Faster Than Expected? Loss of ice, melting of permafrost and other climate effects are occurring at an alarming pace.
26.^ Earth May Be Warming Even Faster Than Expected. Three feedback loops are amplifying how rapidly the planet is heating up.
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*************
Seems you don't exactly have your facts straight.
If that were how it works, you'd have a point. Guess what? That's not how it works. Species live in regional climates, and are affected most severely by regional changes. In the Arctic, global warming is having its most profound effects. The changes are severe, and are stressing many species. In the western U.S. we are seeing a severe long-term drought become ever more catastrophic as the air dries and temperatures rise. What kind of effect do you believe these regional changes are having on species? Do you honestly think they are taking it in their stride? In the Siberian Sea, warming sea water is releasing huge quantities of methane (a more potent GHG than CO2) which is not only being released into the atmosphere, but into the sea itself, setting the stage for a massive die off of species as the sea becomes anoxic. When the bulk of the methane stored in the Arctic permafrost is released in the coming decades, what do you think will be the net effect of that event?
This is not a trick question.....
Not a trick answer. Levels of methane in the past;
Atmospheric Concentrations of Greenhouse Gases | Climate Change | US EPA
We have gone from about 780 ppb to 1800 ppb in about a century. In the short term, a decade to a decade and a half, methane is over 100 times as powerful a GHG as CO2. So in effective heating of the atmosphere, we are presently at the equivelent to 500 ppm of CO2.
And the Arctic Ocean is emitting a lot of CH4 right now. An older article, but with very relevant figures. It has not gotten any better.
http://www.lgrinc.com/resources/appnotes/LGR_Case Study-ESAS Methane_032412_R3.pdf
Introduction
Compared to the economic/political hot potato of global warming due to carbon dioxide (CO2), the impact of methane (CH4) on climate change generally receives much less attention and publicity outside the world of environmental science. However, methane has a four times stronger greenhouse effect than CO2, and the result of large methane generation sources, including bovine agriculture, waste landfills and naturally formed bio-geological sediments, cannot be omitted from any detailed climate model. Now, recent studies by a collaborative team of Russian, American and Swedish researchers have revealed the significant extent of methane leakage from a massive undersea reserve trapped in East Siberian Arctic Shelf (ESAS) sediments, bringing worldwide and web wide attention to yet another possible negative consequence of continued ocean warming. These measured venting rates are already unprecedented, and on a par with the total methane venting flux from the entire World Ocean (see for example SCIENCE, 5 March 2010 Vol. 327 and http://news. yahoo.com/blogs/sideshow/giant-plumes-methane-bubblingsurface- arctic-ocean-163804179.html).
Historically? Methane levels have more than doubled, as has already been pointed out. And from a physics point of view, frozen methane tends to stay frozen unless it is warmed. And a recent report has indicated, even more so than previous papers, that the economic cost of methane release in the Arctic could be staggering.
Costs of Arctic methane release could approach value of global economy ? study
http://www.nature.com/nature/journal/v499/n7459/pdf/499401a.pdf
Historically? Methane levels have more than doubled, as has already been pointed out. And from a physics point of view, frozen methane tends to stay frozen unless it is warmed. And a recent report has indicated, even more so than previous papers, that the economic cost of methane release in the Arctic could be staggering.
Costs of Arctic methane release could approach value of global economy ? study
http://www.nature.com/nature/journal/v499/n7459/pdf/499401a.pdf
Still havn't answered the question. When did the methane release begin?
The increase in global atmospheric methane concentrations had slowed down for a while, but has picked up again since 2006, as reported by the World Meteorological Organization (via ClimateProgress):
Methane (CH4) contributes about 18% to the overall global increase in radiative forcing since 1750 and is the second most important greenhouse gas after carbon dioxide.
Before the start of the industrial era, atmospheric methane was about 700 parts per billion (number of molecules of the gas per billion molecules of dry air) Since 1750, it has increased 158%, mostly because of activities such as cattle-rearing, rice planting, fossil fuel exploitation and landfills. Human activities now account for 60% of methane emissions, with the remaining 40% being from natural sources such as wetlands.
After a period of temporary relative stabilization from 1999 to 2006, atmospheric methane has again risen. Scientists are conducting research into the reasons for this, including the potential role of the thawing of the methane-rich Northern permafrost and increased emissions from tropical wetlands.
Historically? Methane levels have more than doubled, as has already been pointed out. And from a physics point of view, frozen methane tends to stay frozen unless it is warmed. And a recent report has indicated, even more so than previous papers, that the economic cost of methane release in the Arctic could be staggering.
Costs of Arctic methane release could approach value of global economy ? study
http://www.nature.com/nature/journal/v499/n7459/pdf/499401a.pdf
Still havn't answered the question. When did the methane release begin?
Methane has been released in many places around the world nearly since life first began on the planet. That's not the issue. The issue is what we see below:
The increase in global atmospheric methane concentrations had slowed down for a while, but has picked up again since 2006, as reported by the World Meteorological Organization (via ClimateProgress):
Methane (CH4) contributes about 18% to the overall global increase in radiative forcing since 1750 and is the second most important greenhouse gas after carbon dioxide.
Before the start of the industrial era, atmospheric methane was about 700 parts per billion (number of molecules of the gas per billion molecules of dry air) Since 1750, it has increased 158%, mostly because of activities such as cattle-rearing, rice planting, fossil fuel exploitation and landfills. Human activities now account for 60% of methane emissions, with the remaining 40% being from natural sources such as wetlands.
After a period of temporary relative stabilization from 1999 to 2006, atmospheric methane has again risen. Scientists are conducting research into the reasons for this, including the potential role of the thawing of the methane-rich Northern permafrost and increased emissions from tropical wetlands.
And as I've already pointed out, that Arctic research is showing that the permafrost off the northern coast of Siberia is melting and releasing prodigious amounts of CH4.
Historically? Methane levels have more than doubled, as has already been pointed out. And from a physics point of view, frozen methane tends to stay frozen unless it is warmed. And a recent report has indicated, even more so than previous papers, that the economic cost of methane release in the Arctic could be staggering.
Costs of Arctic methane release could approach value of global economy ? study
http://www.nature.com/nature/journal/v499/n7459/pdf/499401a.pdf
