Is this actually global warming?
December 14, 2006 8:58 AM Subscribe
It's December 14th and 56 degrees here in Boston. Everyone is walking around saying, "this is global warming." Is this actually a direct effect of global warming or just part of an abnormal but not potentially life-as-we-know-it ending weather pattern?
There is no way to couple "today's" weather with long-term global climate change. While it is true that a warmer Earth means a higher probability of a warmer day at any given location on any given day, the window of time of a day is way too short to know what's going on with long-term trends.
If your stock went up 10% today, does that mean that it's a clear indication the stock will go up over the next year? Of course not. This is the same principle.
In statistical terms, you cannot tease signal from noise when the true signal operates over years or decades and you are only observing a single day.
but the Earth is getting warmer
posted by mcstayinskool at 9:07 AM on December 14, 2006 [2 favorites]
If your stock went up 10% today, does that mean that it's a clear indication the stock will go up over the next year? Of course not. This is the same principle.
In statistical terms, you cannot tease signal from noise when the true signal operates over years or decades and you are only observing a single day.
but the Earth is getting warmer
posted by mcstayinskool at 9:07 AM on December 14, 2006 [2 favorites]
It's the latter. From what I understand (IANAMeteorologist) there is a high pressure system that is preventing Arctic air from descending into New England, plus we are drawing warmer air from the south.
posted by nekton at 9:18 AM on December 14, 2006
posted by nekton at 9:18 AM on December 14, 2006
What mcstayinskool said. Global warming means a change in climate. Climate and weather aren't the same thing.
posted by nickmark at 9:18 AM on December 14, 2006
posted by nickmark at 9:18 AM on December 14, 2006
I believe the phrase "unseasonably warm" has been in existence a lot longer than "global warming".
People are simply grasping for an opportunity to apply the things they read to their daily life. Right now any very warm or very cold weather is often referred to by the general public as a symptom of that thar global warming they've heard so much about. In the case of extreme cold, that is split between those mentally conjuring the film "The Day After Tomorrow" and those saying, "So much for those 'global warming' theories, har dee har."
There are mild winters and harsh winters, as well as mild periods during harsh winters and vice versa. In other words, this isn't even part of an abnormal pattern, much less a life-altering one. The more control we gain over every single aspect of our own personal indoors environments, the more we become unsettled, inconvenienced, and awed by the unpredictability that is the bread-and-butter of the natural world (and has been from time immemorial).
posted by hermitosis at 9:18 AM on December 14, 2006
People are simply grasping for an opportunity to apply the things they read to their daily life. Right now any very warm or very cold weather is often referred to by the general public as a symptom of that thar global warming they've heard so much about. In the case of extreme cold, that is split between those mentally conjuring the film "The Day After Tomorrow" and those saying, "So much for those 'global warming' theories, har dee har."
There are mild winters and harsh winters, as well as mild periods during harsh winters and vice versa. In other words, this isn't even part of an abnormal pattern, much less a life-altering one. The more control we gain over every single aspect of our own personal indoors environments, the more we become unsettled, inconvenienced, and awed by the unpredictability that is the bread-and-butter of the natural world (and has been from time immemorial).
posted by hermitosis at 9:18 AM on December 14, 2006
Roll a pair of loaded dice, where you chances of getting a 12 are roughly double what they should be.
When a 12 comes up, was it because the dice were loaded, or because sometimes dice just get a 12?
posted by IvyMike at 9:23 AM on December 14, 2006 [3 favorites]
When a 12 comes up, was it because the dice were loaded, or because sometimes dice just get a 12?
posted by IvyMike at 9:23 AM on December 14, 2006 [3 favorites]
Global warming is going to manifest as an increased source of atmospheric energy. This in turn has the potential to cause more extreme weather on both ends of the spectrum. As the average temperature of the Earth increases, that spectrum will show a net movement to a warmer range, but it doesn't mean that local weather won't show extreme cold as well as extreme warmth.
posted by Dipsomaniac at 9:36 AM on December 14, 2006 [1 favorite]
posted by Dipsomaniac at 9:36 AM on December 14, 2006 [1 favorite]
Good analogy IvyMike. With climate change the stakes are higher, and you only get one throw per year as evidence for an emerging pattern.
posted by weapons-grade pandemonium at 9:39 AM on December 14, 2006
posted by weapons-grade pandemonium at 9:39 AM on December 14, 2006
In IvyMike's analogy, I would say that the dice have been coming up 12 for several years now.
posted by bingo at 9:48 AM on December 14, 2006
posted by bingo at 9:48 AM on December 14, 2006
In IvyMike's analogy, I would say that the dice have been coming up 12 for several years now.
Really? Have you compared the weather for the last several years with historic highs and lows?
posted by spicynuts at 10:00 AM on December 14, 2006
Really? Have you compared the weather for the last several years with historic highs and lows?
posted by spicynuts at 10:00 AM on December 14, 2006
Reuters: "This year is set to be the sixth warmest worldwide since records began, stoked by global warming linked to human activities, the British Meteorological Office and the University of East Anglia said on Thursday."
posted by deern the headlice at 10:05 AM on December 14, 2006
posted by deern the headlice at 10:05 AM on December 14, 2006
I will nth the El Nino effect. Here is a New York magazine article that discusses the El Nino effect, as well as predicted climate change and what it means for New York. (I know you are in Boston, but I'm going to guess that extrapolation is possible.)
posted by dame at 10:10 AM on December 14, 2006
posted by dame at 10:10 AM on December 14, 2006
Also, a relevant quote in case people don't feel like reading the whole thing:
"The final ingredient in the mix is global warming. In the past century, the average temperature in New York has risen by two degrees, and the trend shows no sign of slowing down. Indeed, the computer models reviewed in the “Metropolitan East Coast Climate Assessment”—a 50-year prediction of New York’s changing climate, developed by nasa and Columbia University—suggest that the city will continue to heat up by as much as one degree by 2010, two degrees by 2020, and accelerate on a gentle curve until we reach as much as nine degrees warmer than now in 2100. It doesn’t particularly matter whether you believe the warming is man-made or a natural cycle (most, but not all, climatologists believe the former). The point is, pumping that much extra energy into the system is bound to have some effect.
"The impact on our daily life, though, is the big question. A few degrees of warming won’t turn New York into a Miami-class shirtsleeves town. The effect will be more subtle: Climate scientists suspect that a warmer climate will produce more weather volatility. It’s not that we’ll have more rain overall, more snow overall, or more storms overall. But each event will be more intense than before."
So basically, global warming has effects, but it is not the prime thing making it 60 this December day.
posted by dame at 10:13 AM on December 14, 2006 [1 favorite]
"The final ingredient in the mix is global warming. In the past century, the average temperature in New York has risen by two degrees, and the trend shows no sign of slowing down. Indeed, the computer models reviewed in the “Metropolitan East Coast Climate Assessment”—a 50-year prediction of New York’s changing climate, developed by nasa and Columbia University—suggest that the city will continue to heat up by as much as one degree by 2010, two degrees by 2020, and accelerate on a gentle curve until we reach as much as nine degrees warmer than now in 2100. It doesn’t particularly matter whether you believe the warming is man-made or a natural cycle (most, but not all, climatologists believe the former). The point is, pumping that much extra energy into the system is bound to have some effect.
"The impact on our daily life, though, is the big question. A few degrees of warming won’t turn New York into a Miami-class shirtsleeves town. The effect will be more subtle: Climate scientists suspect that a warmer climate will produce more weather volatility. It’s not that we’ll have more rain overall, more snow overall, or more storms overall. But each event will be more intense than before."
So basically, global warming has effects, but it is not the prime thing making it 60 this December day.
posted by dame at 10:13 AM on December 14, 2006 [1 favorite]
Climate and weather aren't the same thing.
True. However, the question is whether global warming changes the weather patterns, i.e. the high frequency variability at a local scale. Well, it does. But how we do not really know. This is a highly non-linear system with many possible states of equilibrium. But that question is at the core of current research.
Indeed, god hates math is right I find this sentence offensive in so many ways :) 2006-2007 is an El Niño year apparently, and that explains the weather patterns over eastern US. But as I said, global warming affects El Niño and this is possibly how.
posted by carmina at 10:14 AM on December 14, 2006
True. However, the question is whether global warming changes the weather patterns, i.e. the high frequency variability at a local scale. Well, it does. But how we do not really know. This is a highly non-linear system with many possible states of equilibrium. But that question is at the core of current research.
Indeed, god hates math is right I find this sentence offensive in so many ways :) 2006-2007 is an El Niño year apparently, and that explains the weather patterns over eastern US. But as I said, global warming affects El Niño and this is possibly how.
posted by carmina at 10:14 AM on December 14, 2006
Really? Have you compared the weather for the last several years with historic highs and lows?
Have you?
Cause I very much have.
posted by carmina at 10:16 AM on December 14, 2006
Have you?
Cause I very much have.
posted by carmina at 10:16 AM on December 14, 2006
Really? Have you compared the weather for the last several years with historic highs and lows?
Winters have, on most days, been warmer for the last several years, as I've experienced them, than they have been for the rest of my life going backward. It could be my imagination, but I don't think so, and I'm certainly not the only person who feels this way.
It's no longer online, but the New Yorker did a series last year in which climatologists were quoted saying that Antarctica may not have ice in winter anymore during our lifetime. People are venturing north to see famous glaciers before they melt away. I'm sure that there are many other factors, including El Nino, but the world is also getting warmer in general.
posted by bingo at 10:19 AM on December 14, 2006
Winters have, on most days, been warmer for the last several years, as I've experienced them, than they have been for the rest of my life going backward. It could be my imagination, but I don't think so, and I'm certainly not the only person who feels this way.
It's no longer online, but the New Yorker did a series last year in which climatologists were quoted saying that Antarctica may not have ice in winter anymore during our lifetime. People are venturing north to see famous glaciers before they melt away. I'm sure that there are many other factors, including El Nino, but the world is also getting warmer in general.
posted by bingo at 10:19 AM on December 14, 2006
climatologists were quoted saying that Antarctica may not have ice in winter anymore during our lifetime
You mean the Arctic Ocean, bingo. Antarctica has way too much ice. If all that is gone, we are gone waaay before that.
I agree with the rest of your comment though.
posted by carmina at 10:23 AM on December 14, 2006
You mean the Arctic Ocean, bingo. Antarctica has way too much ice. If all that is gone, we are gone waaay before that.
I agree with the rest of your comment though.
posted by carmina at 10:23 AM on December 14, 2006
Keep in mind that for as warm as it's been in the east, here in Seattle we had a snowstorm and the coldest night in eight years right at the end of November, following on the all-time record rainfall at Sea-Tac. And later today, one of the nastiest extratropical lows to hit the Northwest in many years. The typical El Niño weather pattern still hasn't set up in the Northwest. If anything, it's been more like La Niña weather.
My analogy for people who say "It's cold today, global warming is a myth" is akin to someone watching an old Bears game, seeing Walter Payton get tackled behind the line of scrimmage, and saying, "Payton didn't gain any yards, there's no way he was one of the greatest running backs in NFL history."
It's not the data points, it's the curve.
posted by dw at 10:25 AM on December 14, 2006
My analogy for people who say "It's cold today, global warming is a myth" is akin to someone watching an old Bears game, seeing Walter Payton get tackled behind the line of scrimmage, and saying, "Payton didn't gain any yards, there's no way he was one of the greatest running backs in NFL history."
It's not the data points, it's the curve.
posted by dw at 10:25 AM on December 14, 2006
Warm weather in the winter is caused by global warming just as much as our lack of hurricanes and cooler summer (at least in DC) is attributed to global cooling.
posted by aznhalf at 10:28 AM on December 14, 2006
posted by aznhalf at 10:28 AM on December 14, 2006
it's 56º here in southern vermont today. according to vermont's npr news station this morning, in 1901 there was a record setting high of 63º in burlington - northern vermont is typically cooler than southern.
so yeah, it's just a warm year. next year it could be -17º today - just the luck of the draw.
posted by sporky at 10:35 AM on December 14, 2006
so yeah, it's just a warm year. next year it could be -17º today - just the luck of the draw.
posted by sporky at 10:35 AM on December 14, 2006
I think that the anecdotal is starting to add up to and reflect the actual. It still won't pass muster as scientific evidence, but you can now see local changes as a result of the global phenomenon. For example, species ranges are moving steadily north. That must correspond to temperature ranges also moving northward.
I haven't been able to find much on changes in snowfall and milder winters, but anecdotally, my hometown in Southern Illinois used to receive a pretty good amount of snow(15-30") every winter, but now it falls on the rain side of most storms, and the last few winters have been almost snowless. Of course, in other places the changes might be in the opposite direction, since the global rise in average temperature will have wildly varying local effects. None of those observations themselves are enough, but when you look at them in the larger context of what we know is happening to the global climate, it's hard not to think that a lot of the unusual things we're seeing are related to it. Probably some are, and others are just the usual randomness of local, short-term weather patterns, and it's not easy to tease out which is which. Time will tell.
posted by jdunn_entropy at 10:37 AM on December 14, 2006
I haven't been able to find much on changes in snowfall and milder winters, but anecdotally, my hometown in Southern Illinois used to receive a pretty good amount of snow(15-30") every winter, but now it falls on the rain side of most storms, and the last few winters have been almost snowless. Of course, in other places the changes might be in the opposite direction, since the global rise in average temperature will have wildly varying local effects. None of those observations themselves are enough, but when you look at them in the larger context of what we know is happening to the global climate, it's hard not to think that a lot of the unusual things we're seeing are related to it. Probably some are, and others are just the usual randomness of local, short-term weather patterns, and it's not easy to tease out which is which. Time will tell.
posted by jdunn_entropy at 10:37 AM on December 14, 2006
Can someone clarify this el Nino thing? My reading of it is that when certain weather conditions occur, this is called el Nino, rather than vice versa, that el Nino somehow causes these weather conditions. If this is the case, how is el Nino dispositive regarding the OP's question?
Personally, I would say that here in Maine the weather has been different over the past few years. Seems like an awfully funny coincidence if that's not somehow connected to overall climate change, notwithstanding the climate/weather distinction.
posted by miss tea at 10:39 AM on December 14, 2006
Personally, I would say that here in Maine the weather has been different over the past few years. Seems like an awfully funny coincidence if that's not somehow connected to overall climate change, notwithstanding the climate/weather distinction.
posted by miss tea at 10:39 AM on December 14, 2006
dw, word up.
aznhalf, are you being snarky? Hurricanes is a big, big issue and possibly one of the hottest topics in climate research. There are some sceptics of the idea of hurricane enhancement from within the scientific community who nevertheless accept global warming as a fact.
sporky, I do not have Vermont temps handy right now, but the question is how many warm days like that did you have in 1901 vs in 2006. That's what raises the annual (or even seasonal) mean temperature noticeably.
posted by carmina at 10:40 AM on December 14, 2006
aznhalf, are you being snarky? Hurricanes is a big, big issue and possibly one of the hottest topics in climate research. There are some sceptics of the idea of hurricane enhancement from within the scientific community who nevertheless accept global warming as a fact.
sporky, I do not have Vermont temps handy right now, but the question is how many warm days like that did you have in 1901 vs in 2006. That's what raises the annual (or even seasonal) mean temperature noticeably.
posted by carmina at 10:40 AM on December 14, 2006
have those too - we had the warmest november in vermont since records were started, but only slightly. as far as december goes, it is far too early.
posted by sporky at 10:43 AM on December 14, 2006
posted by sporky at 10:43 AM on December 14, 2006
scary, huh?
Anything can be scary, depending on the scale. That is not even a degree of a change. And yes, a degree of change can have great effects, but it is NOT the main reason it is near 60 today.
posted by dame at 10:44 AM on December 14, 2006
Anything can be scary, depending on the scale. That is not even a degree of a change. And yes, a degree of change can have great effects, but it is NOT the main reason it is near 60 today.
posted by dame at 10:44 AM on December 14, 2006
carmina wrote: 2006-2007 is an El Niño year apparently
It's true that there's a positive El Niño this year, but the weather's behavior has not been typical. Normally you'd expect to see storms coming through southern California, but the storms this year have stayed considerably north, coming ashore in Oregon and Washington. Nobody really seems to understand this.
Warmth in the East seems more to be due to a positive North Atlantic Oscillation. Again, nobody seems to know why it's been positive more than negative recently, if that has anything to do with Global Warming or not. Recent predictions show that the NAO might be headed down, so cooler weather could start within a week or two.
Recent studies by the UNH Climate Change Research Center suggest that while the net temperature increase in New England over the last half century has been about a degree, winter temperatures are up more like 4-5 degrees. So it might not be such a stretch for someone to say that they don't feel like winter has been as harsh recently as it used to be, although there will continue to be both oddly warm and oddly cold winters.
One more point of correction, Arctic ice is disappearing in Summer, not winter.
posted by dseaton at 10:44 AM on December 14, 2006
It's true that there's a positive El Niño this year, but the weather's behavior has not been typical. Normally you'd expect to see storms coming through southern California, but the storms this year have stayed considerably north, coming ashore in Oregon and Washington. Nobody really seems to understand this.
Warmth in the East seems more to be due to a positive North Atlantic Oscillation. Again, nobody seems to know why it's been positive more than negative recently, if that has anything to do with Global Warming or not. Recent predictions show that the NAO might be headed down, so cooler weather could start within a week or two.
Recent studies by the UNH Climate Change Research Center suggest that while the net temperature increase in New England over the last half century has been about a degree, winter temperatures are up more like 4-5 degrees. So it might not be such a stretch for someone to say that they don't feel like winter has been as harsh recently as it used to be, although there will continue to be both oddly warm and oddly cold winters.
One more point of correction, Arctic ice is disappearing in Summer, not winter.
posted by dseaton at 10:44 AM on December 14, 2006
miss tea, El Nino is a phenomenon that starts in the Pacific Ocean and involves very specific change in the sea surface temperature and sea level pressure there only. Later on the disturbance expands and affects the rest of the globe affecting the weather locally. More information you can find here.
posted by carmina at 10:45 AM on December 14, 2006
posted by carmina at 10:45 AM on December 14, 2006
miss tea, from the link (which is a really clear article):
"In June and July, government satellites and thermal buoys that track the heat of the ocean detected a huge mass of bathtub-warm water forming off the coast of Indonesia and Sri Lanka. By August, it had broken loose and begun to migrate across the ocean, headed toward Peru. The normally chilly waters of the Pacific gradually warmed and warmed, until by September the water along the entire equator—a mass twice the size of Europe—was one long ribbon of warm ocean.
"It could mean only one thing: El Niño had returned.
"El Niño—Spanish for “the little boy”—is one of the most powerful natural forces that affect global weather. An El Niño event begins when the trade winds in the Pacific break down. Normally they blow east to west, pushing the sun-warmed water on the surface of the Pacific toward Indonesia, where it piles up offshore and makes that nation particularly rainy and wet. Every two to seven years, though, for reasons that are still a bit mysterious, the trade winds falter. As they slacken, the trades’ grip on this pool of warm ocean-surface water slackens, and it begins to spread across the entire Pacific. A really strong El Niño will warm the coast of Peru by as much as eight degrees."
In pictures.
Basically, El Nino is a phenomenon that begins with one manifestation that has a lot of effects. They aren't sure why it happens.
posted by dame at 10:47 AM on December 14, 2006
"In June and July, government satellites and thermal buoys that track the heat of the ocean detected a huge mass of bathtub-warm water forming off the coast of Indonesia and Sri Lanka. By August, it had broken loose and begun to migrate across the ocean, headed toward Peru. The normally chilly waters of the Pacific gradually warmed and warmed, until by September the water along the entire equator—a mass twice the size of Europe—was one long ribbon of warm ocean.
"It could mean only one thing: El Niño had returned.
"El Niño—Spanish for “the little boy”—is one of the most powerful natural forces that affect global weather. An El Niño event begins when the trade winds in the Pacific break down. Normally they blow east to west, pushing the sun-warmed water on the surface of the Pacific toward Indonesia, where it piles up offshore and makes that nation particularly rainy and wet. Every two to seven years, though, for reasons that are still a bit mysterious, the trade winds falter. As they slacken, the trades’ grip on this pool of warm ocean-surface water slackens, and it begins to spread across the entire Pacific. A really strong El Niño will warm the coast of Peru by as much as eight degrees."
In pictures.
Basically, El Nino is a phenomenon that begins with one manifestation that has a lot of effects. They aren't sure why it happens.
posted by dame at 10:47 AM on December 14, 2006
As per NAO, yes, I agree with you that this is a dominant NAtlantic mode of variability. But it is an El Niño year which contributes likewise to the eastern seaboard (Boston) climate as the OP inquired. Atypical response in other areas does not refute El Niño effects. And El Niño/NAO coupling could be the culprit for regional inconsistencies.
As per Arctic ice, correct, within our lifetime it is the summer ice coverage that is in peril. However, winter ice coverage is going down too (used to be very stable) due to global warming feedbacks.
posted by carmina at 10:57 AM on December 14, 2006
As per Arctic ice, correct, within our lifetime it is the summer ice coverage that is in peril. However, winter ice coverage is going down too (used to be very stable) due to global warming feedbacks.
posted by carmina at 10:57 AM on December 14, 2006
Good articles on local changes being observed in the context of global climate change:
Jim Hansen: The Planet in Peril, Pt. 1
Those articles are both parts of really good multipart series, though the remainder of each series is more about what we can do, as opposed to what changes are being observed.
posted by jdunn_entropy at 11:02 AM on December 14, 2006
Jim Hansen: The Planet in Peril, Pt. 1
Studies of more than 1,000 species of plants, animals, and insects, found an average migration rate toward the North and South Poles of about four miles per decade in the second half of the 20th century. That is not fast enough. During the past 30 years the lines marking the regions in which a given average temperature prevails, or isotherms, have moved poleward at a rate of about 35 miles per decade.Elizabeth Kolbert: The Climate of Man, Pt. 1
"It’s very difficult to look at trends in air temperature, because it’s so variable," Romanovsky explained after we were back in the truck, bouncing along toward Deadhorse... "So one year you have around Fairbanks a mean annual temperature of zero"—thirty-two degrees Fahrenheit—"and you say, ‘Oh yeah, it’s warming,’ and other years you have a mean annual temperature of minus six"—twenty-one degrees Fahrenheit—"and everybody says, ‘Where? Where is your global warming?’ In the air temperature, the signal is very small compared to noise. What permafrost does is it works as a low-pass filter. That’s why we can see trends much easier in permafrost temperatures than we can see them in atmosphere.” In most parts of Alaska, the permafrost has warmed by three degrees since the early nineteen-eighties. In some parts of the state, it has warmed by nearly six degreesSo, local changes are definitely already happening, including temperature in the form of isotherms moving northward, but it's really hard to tell whether air temperature changes year-to-year are attributable, though I'd really start to wonder if we continue to have mild winter after mild winter here.
Those articles are both parts of really good multipart series, though the remainder of each series is more about what we can do, as opposed to what changes are being observed.
posted by jdunn_entropy at 11:02 AM on December 14, 2006
hermitosis writes "Right now any very warm or very cold weather is often referred to by the general public as a symptom of that thar global warming they've heard so much about. In the case of extreme cold, that is split between those mentally conjuring the film 'The Day After Tomorrow' and those saying, 'So much for those "global warming" theories, har dee har.'"
One of the things often glossed over is temperature is only a single variable in weather and climate. EG: Phoenix and Mobile experience similar monthly average temperatures (Phoenix is a couple of degrees warmer) but obviously their climate is wildly different because of the amount of rainfall (Mobile has ~8x the rainfall over ~4x as many days).
Also there are more weather cycles than just El Nino and La Nina and sometimes they work at cross purposes. Many locations have a Bi-Polar climate with cycles between lasting upwards of 30 years. In such locations winters/summers are always either hotter than normal or colder than normal because the "normal" is a mathematical construct with conditions that are rarely if ever observed.
Calgary for example has been having fairly mild winters these last few years; however, a friend of mine who is a climate guy says we could see a return to winters of the 60s and early 70s in the next year or two which were generally much colder because of long term cyles in the Pacific.
posted by Mitheral at 11:18 AM on December 14, 2006
One of the things often glossed over is temperature is only a single variable in weather and climate. EG: Phoenix and Mobile experience similar monthly average temperatures (Phoenix is a couple of degrees warmer) but obviously their climate is wildly different because of the amount of rainfall (Mobile has ~8x the rainfall over ~4x as many days).
Also there are more weather cycles than just El Nino and La Nina and sometimes they work at cross purposes. Many locations have a Bi-Polar climate with cycles between lasting upwards of 30 years. In such locations winters/summers are always either hotter than normal or colder than normal because the "normal" is a mathematical construct with conditions that are rarely if ever observed.
Calgary for example has been having fairly mild winters these last few years; however, a friend of mine who is a climate guy says we could see a return to winters of the 60s and early 70s in the next year or two which were generally much colder because of long term cyles in the Pacific.
posted by Mitheral at 11:18 AM on December 14, 2006
Environment Canada has some nice animations of sea surface temperature anomalies that seem to show that there's a lot of warmer than normal water off the east coast right now. Is it caused by global warming? I don't know. But it probably at least partly responsible for the weird weather we're having. (It's well above freezing here in Ottawa as well.)
posted by benign at 12:49 PM on December 14, 2006
posted by benign at 12:49 PM on December 14, 2006
This might be somewhat tangential, but an episode of Penn & Teller: Bullshit! dealt, in part, with the question of whether global warming is actually occuring to the extent that we think it is. Here's a link to the entire episode. (Google video). As great as Penn & Teller are, you have to keep in mind that their analysis may cross the line between skepticism-towards and bias-against the "mainstream."
posted by sentient at 2:50 PM on December 14, 2006
posted by sentient at 2:50 PM on December 14, 2006
Carmina links to a 'scary' graph showing global historic temperature rising dramatically over the last 100-200 years. Yes, that's scary.
The thing is though, history goes back way further than the 1800s. There are cycles and rhythms that affect the planet that take tens of thousands of years to be observed, so a 200 year picture of temperature may not tell the whole story.
This graph is similar, it's global temperature (as well as CO2 levels) but it's over the last 40,000 years. At the very end of it, that tiny little blip, is the sharp rise you can see in carmina's graph. The bigger picture, though, shows that the world has been getting progressively warmer and colder in a very uniform way for a long time.
Yes, humans have definitely played a part, but it's not like the Earth had fine weather every day for 4 billion years and then we came along and ruined it.
To answer the question; no, global warming has only the most marginal affect on today's temperature. If you stand on a beach, you will exert a gravitational pull on the ocean. That doesn't mean you're affecting the tides. As has been said, temperature and climate are very different things.
posted by twirlypen at 4:38 PM on December 14, 2006
The thing is though, history goes back way further than the 1800s. There are cycles and rhythms that affect the planet that take tens of thousands of years to be observed, so a 200 year picture of temperature may not tell the whole story.
This graph is similar, it's global temperature (as well as CO2 levels) but it's over the last 40,000 years. At the very end of it, that tiny little blip, is the sharp rise you can see in carmina's graph. The bigger picture, though, shows that the world has been getting progressively warmer and colder in a very uniform way for a long time.
Yes, humans have definitely played a part, but it's not like the Earth had fine weather every day for 4 billion years and then we came along and ruined it.
To answer the question; no, global warming has only the most marginal affect on today's temperature. If you stand on a beach, you will exert a gravitational pull on the ocean. That doesn't mean you're affecting the tides. As has been said, temperature and climate are very different things.
posted by twirlypen at 4:38 PM on December 14, 2006
My (NYC) Korean manicurist: "That Al Gore guy was right."
posted by CunningLinguist at 4:58 PM on December 14, 2006
posted by CunningLinguist at 4:58 PM on December 14, 2006
hi twirlypen, I put on the last century change in global mean temperature because this comes from very accurate records (direct measurements) and is well understood why it is happening.
In this article you may find some answers for the large variations in global temps that have been reconstructed from the Vostok ice cores:
Changes in terrestrial aerosols hold the key to past climate. More dust was present in glacial periods than during interglacials; this suggests that glacial periods were characterized by extensive deserts, intense surface winds in the desert source regions, and more efficient transport along the imaginary circular path that runs perpendicular to the equator through the poles. This idea of stronger circulation during glacial periods is reinforced by the fact that glacial values of marine aerosols are much higher than interglacial levels. Similar (naturally caused) aerosol loads have not been reported by anyone really for our present climate.
As I said earlier, there are different states of equilibrium that earth's climate can be in, and there is good evidence (through modeling research, clearly our only tool here) that that's what was going on then. The problem is that the antrhopogenic interference might kick the climate back to a different state (easy scenario: change the thermohaline circulation and bring on us a little or large ice age). The Earth will continue to exist, but life will be very different if not impossible for the majority of the biosphere.
My (NYC) Korean manicurist: "That Al Gore guy was right."
My dear Cunning, I believe we go to the same manicurist. I have been preaching on her too!
posted by carmina at 6:50 PM on December 14, 2006
In this article you may find some answers for the large variations in global temps that have been reconstructed from the Vostok ice cores:
Changes in terrestrial aerosols hold the key to past climate. More dust was present in glacial periods than during interglacials; this suggests that glacial periods were characterized by extensive deserts, intense surface winds in the desert source regions, and more efficient transport along the imaginary circular path that runs perpendicular to the equator through the poles. This idea of stronger circulation during glacial periods is reinforced by the fact that glacial values of marine aerosols are much higher than interglacial levels. Similar (naturally caused) aerosol loads have not been reported by anyone really for our present climate.
As I said earlier, there are different states of equilibrium that earth's climate can be in, and there is good evidence (through modeling research, clearly our only tool here) that that's what was going on then. The problem is that the antrhopogenic interference might kick the climate back to a different state (easy scenario: change the thermohaline circulation and bring on us a little or large ice age). The Earth will continue to exist, but life will be very different if not impossible for the majority of the biosphere.
My (NYC) Korean manicurist: "That Al Gore guy was right."
My dear Cunning, I believe we go to the same manicurist. I have been preaching on her too!
posted by carmina at 6:50 PM on December 14, 2006
Thank you, carmina...
When we mean to blame /anthropogenic/ global warming, let's use all three words-if it's cow farts, we're not gonna do much about it...
posted by baylink at 6:38 PM on December 15, 2006
When we mean to blame /anthropogenic/ global warming, let's use all three words-if it's cow farts, we're not gonna do much about it...
posted by baylink at 6:38 PM on December 15, 2006
This thread is closed to new comments.
posted by god hates math at 9:07 AM on December 14, 2006