Perhaps you've heard a friend say, "Okay, I believe climate change is happening, but I'm not a scientist, and don't really understand the science behind it." Well, you don't have to be a scientist to understand it. Look at boiling water. Seriously. What happens when you boil water? You're adding heat to a pot of fluid. The fluid starts moving around as it heats up, eventually evaporating so fast that big boiling bubbles are produced.
Think of Earth as a big ball, covered with a fluid mix of water and air. The sun heats water and air, and some heat becomes motion, moving the air and water around the ball, just like heating moves water in a pot. The long-term patterns of this heating and movements are our climate, changing slowly enough over eons so that most life can adapt to it. But add to this water-air mixture a sudden jolt of heat, and the planetary water cycle suddenly speeds up and changes. This results in bigger and stronger storms and floods. The extra heat creates more extreme heat waves, droughts, and melts ice globally, which raises sea levels. All this is threatening our sources of food, water and shelter, the basics of our survival. Was that a bit fast?
Alright, let's just dissect this a little. How does Earth trap the Sun's heat? Certain gases, like carbon dioxide and water vapor, comprise less than one percent of our atmosphere, but trap direct or reflected sunlight and convert it into heat, releasing it for absorption by air, water and land. The gases can also recapture and release the heat repeatedly. The levels of these so-called greenhouse gases have basically acted like a balanced solar cooker, converting just enough light into heat to create good climatic conditions for our evolution and survival. Until recently, that is.
Burning fossil fuels such as coal, oil and gas for our energy is increasing levels of greenhouse gases, especially carbon dioxide, in the atmosphere, unbalancing our global solar cooker. So, our planet has warmed over one degree Fahrenheit, and will continue to heat further and faster, as more greenhouse gases build up from more burning and feedback effects. Feedbacks? A nasty side-effect of the initial heating from carbon dioxide is that more water evaporates, creating more water vapor, a potent greenhouse gas. Heating is also melting ice globally, turning white, sun-reflecting areas into dark, sunlight-absorbing ones that convert the light to heat. Also, as soil heats, it releases more greenhouse gases, including the very potent greenhouse gas methane (aka natural gas), especially from the Arctic, where global heating is occurring much faster than elsewhere. So heating begets... well, more heating. In fact, most of the heating comes from the feedback effects, not the initial conversion of sunlight to heat.
Viewed from the recent geologic timescale chronicling Earth's climate, humans have added a planetary jolt of heat, souping up the solar cooker. The heat doesn't sound like much, but a little goes a long way towards changing climate. And, actually, the heat isn't that little. Although the total average increase in temperature is small so far, this constant infusion of extra heat is "a lot of energy," says senior climate scientist Warren Washington at the National Center on Atmospheric Research. Just how much? 250-500 million Megawatts of energy. That's the amount of heat that would be produced if we had up to a half million more large power plants on Earth, operating full-time, year after year.
Scientists predict that our planet could heat up another 6 to 11 degrees by the end of this century, roughly the same difference in temperature that separates our climate from the last ice age, when 300-foot thick ice sheets covered the northern U.S. So, our planetary pot of fluids doesn't have to even approach boiling (and probably wouldn't) to dramatically affect our survival.
We're heating our planetary pot of fluids fast, as the animated NASA global map shows. Some of that heat converts to moving energy, which moves fluids, both air and water, around faster. The planetary water cycle is speeding up: more water goes up (evaporation), comes down (rain, especially) and runs off, yearly. In general, the wet gets wetter, the dry, drier -- think droughts and floods, like Texas is experiencing. This more extreme shifting of energy also results in cold getting colder, warm getting warmer (heat waves). Air is also moving faster. This means more energetic storms, from cyclones to hurricanes, and winds speeding up, such as the Antarctic westerlies. And shifting wind patterns: our tropical belts are widening, moving their jet-streams poleward, pushing the dry subtropical climate zone further into the southern U.S. -- read more droughts.
Just like one can't predict the next bubble rising in boiling water, so, too, the planetary scale of climate complexity prevents making detailed, local, climate predictions. But, in general, the outlook is not good. All of the above results in more extreme weather, which will get more extreme as the unbalanced heating continues.
The good news is that we can stop too much harmful climate change if we act fast, and stop emitting global warming gases, mostly by: a) using energy more efficiently; b) switching from fossil fuels to clean renewable energy (solar, wind, geothermal), and c) stopping deforestation. Technically, we can do this. Doing so would create more jobs and improve our economy, as other countries have shown. Bringing our world population down to sustainable levels would also help enormously.
Changing energy sources won't be easy politically, or cheap. But it's cheaper than what we're doing now. We've spent trillions defending foreign oil sources. Fossil fuel pollution and mining inflict heavy costs on human health and our environment. So, even if climate change wasn't happening, it pays for us to switch to renewables and efficiency anyway.
Meanwhile, next time someone tells you they don't understand climate change, tell them to go boil water.
Paul Yeager: Fourth Warmest January in Contiguous U.S., But Record Cold in Alaska
Maj. Gen. Michael R. Lehnert: Top 10 Reasons to Support Clean Energy
Dear Richard2*,
Isn't prominent global warming "skeptic" Dr. Bob Carter committing de facto global warming fraud by misrepresenting increasing global temperature trend lines as flat?**
Isn't that like a climate science scam, a global warming hoax, a blatant and indefensible lie?
If you disagree please provide a scientifically-valid explanation for Bob Carter's gross misrepresentation of scientific data.
Please answer question R2 instead of continuing to run away from it - thank you.
Bob Carter is a leader of and/or major contributor to several of the most prominent organizations that are "skeptical" of man-made global warming, including:
* The Heartland Institute
* The Science and Public Policy Institute (SPPI)
* The Science and Environmental Policy Project (SEPP)
* The Global Warming Policy Foundation (GWPF)
* The Nongovernmental International Panel on Climate Change (NIPCC)
* The International Climate Science Coalition (ICSC)
------------------
* http://en.wikipedia.org/wiki/Astroturfing
** http://scienceblogs.com/deltoid/2011/07/bob_carters_trend_lines.php
Vahrenholt: In my experience as an energy expert, I learned that the Intergovernmental Panel on Climate Change (IPCC) is more of a political than a scientific body. As a rapporteur on renewable energy, I witnessed how thin the factual basis is for predictions that are made at the IPCC. In one case, a Greenpeace activist's absurd claim that 80 percent of the world's energy supply could soon be coming from renewable sources was assumed without scrutiny. This prompted me to examine the IPCC report more carefully.
SPIEGEL: And what was your conclusion?
Vahrenholt: The long version of the IPCC report does mention natural causes of climate change, like the sun and oscillating ocean currents. But they no longer appear in the summary for politicians. They were simply edited out. To this day, many decision-makers don't know that new studies have seriously questioned the dominance of CO2. CO2 alone will never cause a warming of more than 2 degrees Celsius (3.6 degrees Fahrenheit) by the end of the century. Only with the help of supposed amplification effects, especially water vapor, do the computers arrive at a drastic temperature increase. I say that global warming will remain below two degrees by the end of the century. This is an eminently political message, but it's also good news.- Der Spiegel
Vahrenholt is not a climate scientist, and neither is he a real scientific skeptic.
Real climate scientist Hans von Storch reviews the new so-called global warming "skeptic" book that Vahrenholt is peddling:
----------------------
A skeptic lacking skepticism: Fritz Vahrenholt ...
On the web-page of the present book Klimazwiebel and myself are falsely listed as supporters of an explanation by natural variations...
What Vahrenholt presents is a complete explanation of the climate variations, referring to handful of scientists. This explanation is highly complex, with many challenging details, which can hardly be verified by a single person, scientist or lay-person. The interesting detail is that Fritz Vahrenholt is really certain about this “explanation”. Not a bit skeptical... when he comes closer to areas, which I personally have studied, errors emerge, and when I speak to other scientists they say the same for their fields of competence. It seems that Fritz Vahrenholt and his coauthor Sebastian Lüning have simply cherry-picked – what is what they criticize their opponents for.
http://klimazwiebel.blogspot.com/2012/02/skeptic-lacking-skepticism-fritz.html
Dr. Peter Gleick
Feb 5, 2012
The current favorite argument of those who argue that climate changes isn’t happening, or a problem, or worth dealing with, is that global warming has stopped...
The problem with this argument is that it is false: global warming has not stopped and those who repeat this claim over and over are either lying, ignorant, or exhibiting a blatant disregard for the truth...
All of the false claims take advantage of one fundamental truth about the average temperature of our planet: it varies a little, naturally, from year to year. Some years are a bit warmer than average and some are a bit colder than average because of El Niños, La Niñas, cloud variability, volcanic activity... When you filter these out, the human-caused warming signal is clear. But natural variability makes it possible for scurrilous deceivers to... to cherry-pick data to support their claims. They pick particular years or groups of years; they pick particular subsets of data. But when you look at all the data, or when you look at long-term trends, the only possible conclusion is that the Earth is warming...
The next time you hear someone say it isn’t warming, or it hasn’t warmed for “xx” years, or “it’s actually cooling,” remember: someone is trying to deceive you with cherry-picked numbers.
http://tinyurl.com/88f43hl
view the graphic at
http://www.skepticalscience.com/still-going-down-the-up-escalator.html
then read the first 4 paragraphs.
The simple answer is: they have risen, but not by very much. “Our records for the past 15 years suggest the world has warmed by about 0.051C over that period,” said the Met Office. In layman’s terms that is 51 thousandths of a degree.- Jonathan Leake, The Sunday Times
So over the past 15 years the earth has warmed by an average of 3.4 thousandths of a degree!
This reminds one of the Times Atlas story, where it was first claimed that a significant part of Greenlands icecap had melted away. Then, when challenged to prove this, the Times Atlas admitted that the melting was some entirely insignificant amount.
So if there has been no warming for 15 years, doesn't this falsify all the stories about global warming causing numerous horrible things over the past 15 years, stories which were covered unquestioningly by the popular media?
The trend has been there all along, with noise from natural variations imposed on the steady trend.
see the paper by Foster and Rahmsdorf. They filtered out the known natural variations and voila, the original trend line continues right through the past decade.
Foster and Rahmstorf 2011
http://bit.ly/u2CIdp
Foster, Grant, and Stefan Rahmstorf, Global Temperature Evolution 1979–2010, Environ.
Res. Lett., vol. 6, p. 044022, October-December 2011.
Your rhetoric is misleading as usual, Richard2:
1) You cherry-picked the global surface temperature dataset that shows the least warming - other surface datasets show considerably more warming:
http://tinyurl.com/7s9kamc
2) Time interval you cherry-picked includes 1998, which is the year of the strongest El Niño on record.
3) Due to the influence of known external factors including El Ninos and volcanic activity, the time interval you cherry-picked is too short to control for the influence of that "noise" without removing it via standard statistical analysis.
4) When that "noise" is removed via standard standard statistical analysis, "all five [global land and sea] data sets show statistically significant warming even for the time span from 2000 to the present... There is no indication of any slowdown or acceleration of global warming, beyond the variability induced by these known natural factors."
http://iopscience.iop.org/1748-9326/6/4/044022/fulltext/
Given that you post regularly and almost exclusively on this topic, how is it that you Rchard2 are not aware of these basic climate science facts?
Per satellite measurements Greenland lost ~1,764 billion tonnes of ice between March 2003 and and Feb 2011.*
1,764 billion tonnes of ice = 1,764 cubic kilometers of water**, which is larger than the volume of Lake Ontario (1,710 cu km).
Which is to say, according to Richard2 all of the water in Lake Ontario is an "entirely insignificant amount."
Somehow I'm guessing that people who live in the Great Lakes region disagree.
-----------------------
*
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 116, 2011
Revisiting Greenland ice sheet mass loss observed by GRACE
The summed contribution of the complete system yields a mass loss rate and acceleration of −252 ± 28 Gt/yr and −22 ± 4 Gt/yr2 between March 2003 and February 2010
http://www.agu.org/pubs/crossref/2011/2009JB006847.shtml
**
1 Gt ice = 1 gigatonne ice = 1 billion tonnes ice = 1 cubic km water
252 Gt/yr ice * 7 years = 1,764 billion tonnes ice = 1,764 cu km water
"This more extreme shifting of energy also results in cold getting colder"
Where? The IPCC and NASA think the world will get warmer everywhere.
IPCC projections: 2090-2099 relative to 1980-1999
http://www.ipcc.ch/publications_and_data/ar4/syr/en/spms3.html
NASA projections: 2090-2099 relative to 1980-1990
http://www.epa.gov/climatechange/science/futuretc.html#projections
Note that the scale is all positive.
Wrong again.
Did you even bother to try to read and understand the article that I posted just downthread?
Here's a link to that article again, which directly contradicts your false claim:
http://www.independent.co.uk/news/science/science-behind-the-big-freeze-is-climate-change-bringing-the-arctic-to-europe-6358928.html
Grappler: "The IPCC and NASA think the world will get warmer..."
On average.
Grappler: "...everywhere."
On average does not mean "everywhere".
Also the projections you cited are with respect to the last decade of this century, not in all of the "coming years" before then.
HTH.
Wrong again.
http://www.independent.co.uk/news/science/science-behind-the-big-freeze-is-climate-change-bringing-the-arctic-to-europe-6358928.html
Taking the word of weather experts over climate scientists? Interesting.
I do like weather experts though. They may be correct. Who knows?
You again seem confused, Grappler. As the article indicates further down, Professor Stefan Rahmstorf is in fact a climate scientist.
-----------------
The current weather pattern fits earlier predictions of computer models for how the atmosphere responds to the loss of sea ice due to global warming," said Professor Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. "The ice-free areas of the ocean act like a heater as the water is warmer than the Arctic air above it. This favours the formation of a high-pressure system near the Barents Sea, which steers cold air into Europe...
Professor Rahmstorf said the Alfred Wegener study confirms earlier predictions from computer models by Vladimir Petoukhov of the Potsdam Institute, who forecast colder winters in western Europe as a result of melting sea ice.
-----------------------------------------------------------------------------------------
I’ve recently been involved with other scientists and scholars in Utah trying to stop the spread of outright lies, half-truths, abuses of data, and distortions about climate change. Much of this disinformation is coming from (or through) some Republican members of the Utah Legislature...
I'm a Republican myself, and it galls me that my own party has locally fallen for a bunch of conspiracy theories and scientifically incompetent trash. In my opinion, something has to be done to save the party from disaster in the long run...
Democracy depends on accurate information being readily available to the public, and I see people who propagate such disinformation campaigns as enemies of Democracy.
http://bbickmore.wordpress.com/about-this-blog/
Quite the contrary. The cold got warmer ... by a lot.
"In the Arctic, during the 20th century, air temperatures over extensive land areas increased by up to 5°C; sea ice thinned and declined in extent;" Source: IPCC
http://www.ipcc.ch/pdf/assessment-report/ar4/wg2/ar4-wg2-chapter15.pdf
Seems obvious.
Me: "Again, that claim of yours is false."
Grappler: "Quite the contrary. The cold got warmer ... by a lot. 'In the Arctic, during the 20th century, air temperatures over extensive land areas increased by up to 5°C; sea ice thinned and declined in extent;' Source: IPCC"
You seem to not understand that average warming in one region does not mean warming always in everywhere in that region and outside of that region.
"Seems obvious."
Picture Worth 1,000 Obfuscations Dept.:
Here's a graph of NASA data demonstrating that while the Arctic (and the globe) warmed overall during the winter months over the last decade compared to the decade previous to it, PARTS OF Europe, Asia, North America instead cooled:
http://tinyurl.com/7dwf8q7
Again:
Your claim that "a warming earth does not lead to 'cold getting colder' " is false.
http://www.sciencemag.org/content/335/6065/211
Speaking of the IPCC, they also contradict that claim of yours:
IPCC: "it seems more likely than not that there will be an increase in average and extreme wind speeds in northern Europe."
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch11s11-3.html
"Seems obvious."
A loss of sea ice could be a cause of the bitter winds that have swept across the UK in the past week, weather experts say
Steve Connor
Saturday February 4th 2012
The bitterly cold weather sweeping Britain and the rest of Europe has been linked by scientists with the ice-free seas of the Arctic, where global warming is exerting its greatest influence.
A dramatic loss of sea ice covering the Barents and Kara Seas above northern Russia could explain why a chill Arctic wind has engulfed much of Europe and killed 221 people over the past week.
The death toll from Arctic blast has been particularly severe in the Ukraine, where many of the dead have been people sleeping on the streets. Heating and food tents have been set up to ease their hardship. In Romania 24 people are known to have died and 17 in Poland.
A growing number of experts believe complex wind patterns are being changed because melting Arctic sea ice has exposed huge swaths of normally frozen ocean to the atmosphere above.
Continued...
In particular, the loss of Arctic sea ice could be influencing the development of high-pressure weather systems over northern Russia, which bring very cold winds from the Arctic and Siberia to Western Europe and the British Isles, the scientists believe...
"The current weather pattern fits earlier predictions of computer models for how the atmosphere responds to the loss of sea ice due to global warming," said Professor Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. "The ice-free areas of the ocean act like a heater as the water is warmer than the Arctic air above it. This favours the formation of a high-pressure system near the Barents Sea, which steers cold air into Europe."...
Studies by scientists at the Alfred Wegener Institute for Polar and Marine Research have confirmed a link between the loss of Arctic sea ice and the development of high-pressure zones in the polar region, which influence wind patterns at lower latitudes further south. Scientists found that as the cap of sea ice is removed from the ocean, huge amounts of heat are released from the sea into the colder air above, causing the air to rise. Rising air destabilises the atmosphere and alters the difference in air pressure between the Arctic and more southerly regions, changing wind patterns.
Continued...
Professor Rahmstorf said the Alfred Wegener study confirms earlier predictions from computer models by Vladimir Petoukhov of the Potsdam Institute, who forecast colder winters in western Europe as a result of melting sea ice.
Dr Petoukhov and his colleague Vladimir Semenov were among the first scientists to suggest a link between the loss of sea ice and colder winters in Europe. Their 2009 study simulated the effects of disappearing sea ice and found that for some years to come the loss will increase the chances of colder winters.
http://www.independent.co.uk/news/science/science-behind-the-big-freeze-is-climate-change-bringing-the-arctic-to-europe-6358928.html
------------------------------------------------------------------------
The Earth's climate is now clearly out of balance and is warming. Many components of the climate system—including the temperatures of the atmosphere, land and ocean, the extent of sea ice and mountain glaciers, the sea level, the distribution of precipitation, and the length of seasons—are now changing at rates and in patterns that are not natural and are best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century…
In the next 50 years, even the lower limit of impending climate change—an additional global mean warming of 1°C above the last decade—is far beyond the range of climate variability experienced during the past thousand years and poses global problems in planning for and adapting to it. Warming greater than 2°C above 19th century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity, and—if sustained over centuries—melting much of the Greenland ice sheet with ensuing rise in sea level of several meters. If this 2°C warming is to be avoided, then our net annual emissions of CO2 must be reduced by more than 50 percent within this century.
http://www.agu.org/sci_pol/positions/climate_change2008.shtml
Per overwhelming scientific evidence the Earth would have, averaged over time, continued its slow cooling trend over the past several thousand years were it not for the rapid build-up of man-made greenhouse gases in the atmosphere since the dawn of the industrial revolution.
Known natural forcing agents of historical global warming - including changes in orbital cycles and increases in solar radiative output - cannot explain the bulk of the observed global warming over recent decades.
Neither has any scientific theory or hypothesis to explain the bulk of recent warming other than AGW theory survived scientific scrutiny.
As to what and when.
Learn a little geology
The warmers do not understand the basics
It sounds like children playing at cooking.
Learn your geology
Stop your fearmongering
The relevant analogy globally is to adding a duvet in bed, or better, to adding a foil blanket.
Ice age temperatures were about 5 degrees cooler than today, not 10 degrees. A 10-degree shift this century is a huge change, and unlikely to be seen. A global 2-3 degree shift would be quite enough to worry about.
The extra equivalent heating power of the blanket (not energy) is about 0.3% of the sun's input, which explains neatly why global temperature has risen by about 0.07% - or about 0.2 degrees so far.
Even as a messaging tool, using an inappropriate analogy or getting important details wrong just gives fuel to the deniers. Your arguments are in principle sound, but they may backfire - it's very hard to idiotproof a message when faced with such an excellent range of idiots as opponents.
Yes there is, via: evaporization, condensation, freezing and melting.
ThinkCreeps: "Ice age temperatures were about 5 degrees cooler than today, not 10 degrees."
When Harte said "6 to 11 degrees" she was referring to degrees Fahrenheit; you are referring to Celsius.
ThinkCreeps: "global temperature has risen by... about 0.2 degrees so far."
The global temperature has risen by about 0.7 degrees C since the 1960's, or about 1.3 degrees F.
---------------------------
Aside to Ms. Harte: Please tell your husband that one of his former students says "Hi". :-)
http://www.ncdc.noaa.gov/paleo/ctl/100k.html
That is, there was a much larger gradient from equator to pole. Winds were undoubtedly stronger back then.
That is, there was a much larger gradient from equator to pole. Winds were undoubtedly stronger back then."
And your point with respect to the current relatively very rapid global warming trend that will warm the Earth to levels never before experienced by human civilization is what, exactly?
As the Cretaceous Period shows, a warming earth does not lead to "cold getting colder" or "air moving faster".
Three source help explain why:
During the Cretaceous Period, "leaf fossils, mosasaurs, pleisiosaurs, dinosaurs, marsupials, and diverse assemblages of mollusks added to a growing body of evidence that polar temperatures in the deep past were warm and the equator-to-pole thermal gradient was low."
http://www.sciencemag.org/content/282/5397/2199.full
Note the low thermal gradient. That is the key. The strength of the jet stream is augmented by a high "equator-to-pole thermal gradient". That is why the jet stream is so strong in the winter ... high thermal gradient.
"During the winter months, when the equator-to-pole temperature disparity is at its greatest, the jet stream reaches its maximum velocity."
http://www.scientificamerican.com/article.cfm?id=what-causes-the-high-spee
During the Cretaceous Period, "A very gentle temperature gradient from the equator to the poles meant weaker global winds, contributing to less upwelling and more stagnant oceans than today. This is evidenced by widespread black shale deposition and frequent anoxic (oxygen-depleted) events."
http://www.nps.gov/prwi/naturescience/upload/A%20Petrified%20Prospectus.pdf
The "boiling water" example doesn't quite capture the real science behind our global winds.
Your Cretaceous Period examples demonstrate no such thing.
Your examples are with respect to a geological period when Earth the was far warmer than today; they do not however address the specific condition of when the Earth is *warming* relatively very rapidly.
Do you have a source for that?
Here is the problem. Temperature gradients are the primary driver of winds. There is both a vertical gradient and a equator-to-polar gradient. Both are shrinking due to global warming. That is, over time, the poles aren't as cold relative to the equator and the troposphere isn't as cold relative to the surface. In both dimensions, gradients are reduced.
Expect winds to slow down. Science shows why.
"By way of definition, a jet in fluid dynamics is simply a core (or 'stream') of fluid moving at a higher velocity than the surrounding fluid. Although they are complicated to describe mathematically, the jet streams in the atmosphere are a straightforward, natural result of the meridional (that is, equator-to-pole) temperature gradient in the earth's atmosphere. Analogous flows exist on other planets with substantial atmospheres having similar temperature gradients."
http://www.scientificamerican.com/article.cfm?id=what-causes-the-high-spee
Troposphere warming faster than surface
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/figure-3-18.html
Poles warming faster than equator
http://www.science.unsw.edu.au/news/wetlands-are-bad-and-good-news-for-arctic-warming-study/
Is that a joke?
I was referring to YOUR sources.
Grappler: "Here is the problem. Temperature gradients are the primary driver of winds. There is both a vertical gradient and a equator-to-polar gradient. Both are shrinking due to global warming. That is, over time, the poles aren't as cold relative to the equator and the troposphere isn't as cold relative to the surface. In both dimensions, gradients are reduced."
If we were talking about a system in equilibrium then your argument would have more merit. However, the scientific fact that the globe is warming relatively very rapidly does indeed lead to regions with "cold getting colder".
For example:
As the Arctic heats up Arctic ice is melting at an accelerating rate, which in lowers the amount of ice that reflects the Sun's rays at an accelerating rate, which in turn increases the amount of the Sun's energy that absorbed by the Arctic Ocean at an accelerating rate. As the Arctic Ocean warms relatively rapidly the temperature gradient with the air above the Arctic ocean increases, creating a high pressure system. This high pressure system forces the Arctic air southwards, making winter conditions more extreme than usual in parts of Europe, North Asia, and North America.
HTH.
We'll have a bright sun and an atmosphere not thicker than we have now but that is somewhat more opaque at the equator, but not significantly more opaque at the poles. That's going to result higher temperature gradients and stronger winds. A high equator to pole gradient is the price we pay for a bright sun.
We aren't going to get Cretaceous climate. We can't. If we pump enough CO2 to have humid summer-ice-free poles and Cretaceous climate, we'll probably hit runaway. If you want that climate again, you'll need to make the sun dimmer.
http://www.igsb.uiowa.edu/Mapping/greenhse/grnhouse.htm
Four times current CO2 levels. (>1500 ppm)
11.2 degree F warmer (6.2 degrees C)
Regardless, we are already seeing the reduced gradient and a shifting of the jet stream toward the poles.
Were the last two million years of ice ages a myth? Who knew?
Of course not.
Where did you get the incorrect notion that what you quoted implies otherwise?
"just enough light"
"good climatic conditions"
It all implies a steady climate with balanced solar energy influx with just enough light to create steady climate conditions. Conversely, we've seen tremendous ice age cycles for over 2 million years.
I think I see the disconnect here.
My read is Dr. Harte is saying that atmospheric greenhouse gas concentrations have, during he current geological epoch -- the Holocene -- been integral to creating the relatively very steady climate conditions that characterize this current epoch. It is entirely within the relatively very "good climatic conditions" of the current geological epoch that human civilization has "evolved" and survived" - flourished, even. And by my read what Dr. Harte is saying is scientifically consistent and correct.
I see now that another interpretation of her words however is with "evolve" and "survive" being in reference to humans as a species, not human civilization. That interpretation however is as you say not in agreement with the fact that there have been ice ages, which is why I didn't read it that way. As Dr. Harte is no doubt well aware of the glacial-interglacial cycles of the previous geological epoch -- the Pleistocene -- I believe my read with respect to the intent of her wording is correct.
So is warming the mean temperature of the Earth to a level far higher than ever experienced in the history of human civilization.
If we do nothing to address climate change, per overwhelming scientific evidence one of these scenarios is very likely to happen, while the other scenario will almost certainly not happen.
Question to Grappler:
Do you know which scenario is which? Based on your rhetoric it's kinda hard to tell.
People should be interested in which cities will disappear.
The first to pack up will experiences the lowest investment losses.
A 100 year plan makes sense to me because I sense that people are able to think in blocks of time that large. For example, most people are able to picture the 20th century as a complete whole. Try to do that with 2 or 3 centuries and it doesn't work.
Two things add to this. First, a 100 plus year lifespan is becoming more common, and thus more ponderable. Second, the very act of having a hundred year plan will lead to behavioral changes that will reduce climate emissions. In other words, the existence of a plan helps to eliminate the need for a plan.
Because it is too cold for humans.
http://tinyurl.com/82jxfo8
When the temperature starts rising because of the end of La Nina are you going to keep making the same claims?
Projections of future warming are based on far more than computer models. Indeed, a temperature rise based on empirical data and no computer models yields a HIGHER temperature projection than most computer models do.
hardycross: "...which have ALL been proven wrong."
Wrong again.
http://www.realclimate.org/index.php/archives/2011/01/2010-updates-to-model-data-comparisons/