Sorry to be such a pedant but Venus is about 0.95% the size of the Earth. The atmosphere is much denser but I'm not sure it's that much bigger in size than Earth's.
I basically agree with your assessment of what happens the the permafrost melts although some of it will decompose aerobically releasing CO2 rather than CH. I'm not sure it will happen as fast as you think it may based on what I've heard scientists say about it but even they say there could be non-linear processes they don't know about so you may be right.
12 years is a climatologically insignificant length of time in which natural variation can easily overwhelm the global warming signal. Things like the lower than normal solar cycle we are in right now and the series of La Nina years lately can have that effect. If the 1998 temperature record has not been broken by 2020 then you might have something there.
From the National Snow & Ice Data Center's Arctic Sea Ice News web site (March 6th update):
Average sea ice extent for February 2013 was 14.66 million square kilometers (5.66 million square miles). This is 980,000 square kilometers (378,000 square miles) below the 1979 to 2000 average for the month, and is the seventh-lowest February extent in the satellite record. Since 2004, the February average extent has remained below 15 million square kilometers (5.79 million square miles) every year except 2008. Prior to 2004, February average extent had never been less than 15 million square kilometers. Ice extent remains slightly below average everywhere except the Bering Sea.
Doesn't sound like Arctic ice is making a comeback to me.
The Antarctic sea ice maximum has increased somewhat but only about 1/4 as much as the Arctic sea ice minimum has declined. Since Antarctic sea ice melts completely away every year it doesn't stay above average ever but drops back to a average of 0 every year. Meanwhile the Antarctic ice sheet continues to lose ice.
As the AC above said reality just is. But conservatives have their ideas about how the world should be and are resistant to things that run counter to their worldview. Liberals are more go with the flow types who are more able to adjust their worldview when circumstances warrant it.
It's generally agreed that the cyclical cause of the glaciations is Milankovitch cycles. None of the various Milankovitch cycles is fast acting enough to account for the rise in temperatures in the last 100+ years.
The equator is not likely to become a desert. Look up Hadley Cells for more information. Basically what happens is that air rises at the equator and as it rises it cools and releases water in the form of precipitation keeping the equatorial region pretty wet in general. That risen air then travels north and south and comes down around 30 degrees north and south as cooler, drier air. Those areas are where the great deserts of the Earth are located. The effects of global warming on this would be to somewhat strengthen that Hadley circulation moving the norther/southernmost desert areas slightly further from the equator.
One thing to keep in mind is that as you get further north on the globe the longitude lines get closer together reducing the total area of land available.
Siberia and Canada may become somewhat warmer on average but the length of the days isn't going to change and it will still be damn cold in the middle of winter there.
You are right about this being a very large experiment with no guarantees as to what the outcome will be.
I'm not that concerned that humans will survive. After all we've managed to make a life in places as diverse as the Kalahari Desert and the high Arctic. As long as some of us can find food and shelter the species will survive. Other species are adapting, the question is can they adapt fast enough to survive. We'll find out.
The scientific examination of natural drivers of climate says that we should actually be slightly cooling. They estimate that human caused increases in greenhouse gases in the atmosphere are responsible for 80-120% of global warming in the recent past.
The interesting thing about isostatic rebound is that there is a see-saw effect. When the massive ice sheets were in place their weight caused a depression of the land under them but it also caused the land to the south* of them to bulge up. Now with the ice sheets gone the depressed areas are rebounding while the areas that bulged up are dropping back down.
If you really think increases in plant growth can offset CO2 from burning fossil fuels that took millions of years for plants to accumulate I've got a bridge in Brooklyn to sell you. It helps but it's not enough by itself.
No, climatologists have always used 30 year running means since it was defined by the World Meteorological Organization as the standard for measuring climate which was before the IPCC was formed in 1988. Here's a FAQ from the WMO on climatology.
Nothing wrong with the chart but maybe there is with your interpretation of it. A 5 year running mean is not particularly significant climatologically. Climatologist usually work with 30 year running means.
The massive industrialization that occurred during that time period caused a huge increase in aerosols until pollution controls started being applied in the late 1960's and early 1970's had something to do with it. Also, the Sun quit increasing it's strength as it had through the earlier part of the 20th century.
Africa may bypass building up the kind of infrastructure we have in the western world and go straight to a wireless world with local solar power to charge their devices.
Except the simple assumption that it's been warming since the end of the last glaciation is wrong. Temperatures hit a peak about 8,000 years ago during the Holocene Climatic Optimum and have generally been cooling ever since.
Problem is at the rate temperatures are increasing they will be higher than 100% of the past 11,300 years (and actually at least the past 100,000 years) within 50 years.
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Sorry for piling on. We're all guilty of engaging our mouths before we engage our brain at one time or another so no biggie.
Sorry to be such a pedant but Venus is about 0.95% the size of the Earth. The atmosphere is much denser but I'm not sure it's that much bigger in size than Earth's.
I basically agree with your assessment of what happens the the permafrost melts although some of it will decompose aerobically releasing CO2 rather than CH. I'm not sure it will happen as fast as you think it may based on what I've heard scientists say about it but even they say there could be non-linear processes they don't know about so you may be right.
You talk a lot about weather and not much about climate. I've seen no evidence that climate scientists are ignoring evidence.
12 years is a climatologically insignificant length of time in which natural variation can easily overwhelm the global warming signal. Things like the lower than normal solar cycle we are in right now and the series of La Nina years lately can have that effect. If the 1998 temperature record has not been broken by 2020 then you might have something there.
From the National Snow & Ice Data Center's Arctic Sea Ice News web site (March 6th update):
Average sea ice extent for February 2013 was 14.66 million square kilometers (5.66 million square miles). This is 980,000 square kilometers (378,000 square miles) below the 1979 to 2000 average for the month, and is the seventh-lowest February extent in the satellite record. Since 2004, the February average extent has remained below 15 million square kilometers (5.79 million square miles) every year except 2008. Prior to 2004, February average extent had never been less than 15 million square kilometers. Ice extent remains slightly below average everywhere except the Bering Sea.
Doesn't sound like Arctic ice is making a comeback to me.
The Antarctic sea ice maximum has increased somewhat but only about 1/4 as much as the Arctic sea ice minimum has declined. Since Antarctic sea ice melts completely away every year it doesn't stay above average ever but drops back to a average of 0 every year. Meanwhile the Antarctic ice sheet continues to lose ice.
As the AC above said reality just is. But conservatives have their ideas about how the world should be and are resistant to things that run counter to their worldview. Liberals are more go with the flow types who are more able to adjust their worldview when circumstances warrant it.
It's generally agreed that the cyclical cause of the glaciations is Milankovitch cycles. None of the various Milankovitch cycles is fast acting enough to account for the rise in temperatures in the last 100+ years.
The further north you get the more atmosphere the sunlight has to travel through and the more ground area a given patch of sunlight has to cover.
Also, the winters will still be very cold which will keep some biennials and perennials from ever growing there.
You toss that off glibly but there is evidence that the amount of plankton in the oceans has dropped considerably since the 1950's.
The equator is not likely to become a desert. Look up Hadley Cells for more information. Basically what happens is that air rises at the equator and as it rises it cools and releases water in the form of precipitation keeping the equatorial region pretty wet in general. That risen air then travels north and south and comes down around 30 degrees north and south as cooler, drier air. Those areas are where the great deserts of the Earth are located. The effects of global warming on this would be to somewhat strengthen that Hadley circulation moving the norther/southernmost desert areas slightly further from the equator.
One thing to keep in mind is that as you get further north on the globe the longitude lines get closer together reducing the total area of land available.
There's still a sign on I-5 out north of town near Chemawa School.
Siberia and Canada may become somewhat warmer on average but the length of the days isn't going to change and it will still be damn cold in the middle of winter there.
You are right about this being a very large experiment with no guarantees as to what the outcome will be.
I'm not that concerned that humans will survive. After all we've managed to make a life in places as diverse as the Kalahari Desert and the high Arctic. As long as some of us can find food and shelter the species will survive. Other species are adapting, the question is can they adapt fast enough to survive. We'll find out.
The scientific examination of natural drivers of climate says that we should actually be slightly cooling. They estimate that human caused increases in greenhouse gases in the atmosphere are responsible for 80-120% of global warming in the recent past.
The interesting thing about isostatic rebound is that there is a see-saw effect. When the massive ice sheets were in place their weight caused a depression of the land under them but it also caused the land to the south* of them to bulge up. Now with the ice sheets gone the depressed areas are rebounding while the areas that bulged up are dropping back down.
*In the northern hemisphere.
You got that bass-ackwards son. The Arctic is ocean, Antarctica is a continent.
If you really think increases in plant growth can offset CO2 from burning fossil fuels that took millions of years for plants to accumulate I've got a bridge in Brooklyn to sell you. It helps but it's not enough by itself.
No, climatologists have always used 30 year running means since it was defined by the World Meteorological Organization as the standard for measuring climate which was before the IPCC was formed in 1988. Here's a FAQ from the WMO on climatology.
Tell me in what quantifiable ways it is going to effect our lives on this planet.
The IPCC AR4 Working Group 2 report is a good summary of how it is expected affect our lives. The updated AR5 report is due out in October.
Your understanding of what the models have projected is lacking. Here is a comparison of model output to observations through 2012. The models are doing that bad.
Nothing wrong with the chart but maybe there is with your interpretation of it. A 5 year running mean is not particularly significant climatologically. Climatologist usually work with 30 year running means.
The massive industrialization that occurred during that time period caused a huge increase in aerosols until pollution controls started being applied in the late 1960's and early 1970's had something to do with it. Also, the Sun quit increasing it's strength as it had through the earlier part of the 20th century.
Africa may bypass building up the kind of infrastructure we have in the western world and go straight to a wireless world with local solar power to charge their devices.
Except the simple assumption that it's been warming since the end of the last glaciation is wrong. Temperatures hit a peak about 8,000 years ago during the Holocene Climatic Optimum and have generally been cooling ever since.
Problem is at the rate temperatures are increasing they will be higher than 100% of the past 11,300 years (and actually at least the past 100,000 years) within 50 years.