....

[skierinvermont]

And let me just say that I'm not arguing that we caused 0% increase in this study. Of course a warmer climate can allow for more water vapor eventually. We probably have some say in that. The problem I have is the shear confidence they display saying that the increase we see is all because of AGW. I'm on the side that mother nature and her natural cycles likely had much more to do with it then the article suggests. Many of our large precip events are caused by an anomalous blocking pattern. If you want to argue blocking is because of climate change..that is another argument, but this isn't what the article is stating. A stalled front that drops heavy rain simply can't be directly tied to AGW. We simply do not have the ability to determine that. Also, what about the rest of the globe? Is everyone seeing this? What about decadal cycles? That is going to have a say in precip amounts and 60 years isn't going to cover 2 back to back cycles of any oscillation so that we can try to even make out a trend. You have to think about all these things. This is OT, but even something like tropical ACE is having a say in climate by some mets and scientists. You have very low tropical ACE..something that is supposed to take oceanic heat and transport it north. Well all that heat has to go somewhere and it may be contributing to the mid latitude heat waves we've been having across the world. There are just so many questions we need answered. Pretty pics of cars submersed and a graph that tries to show increased precip that may be skewed by stations isn't quite enough. That's great the US has seen many warm years since 2000, but that's not nearly as extreme across the globe.

I think there is some confusion because you're not distinguishing properly between individual events vs trends. There is a trend of increased heatwaves and of downpours. The trends can probably be attributed to AGW (definitely for the increased trend of heatwaves). As for individual events, it can get much more complicated because you get into basically almost butterfly effect questions. All events are changed/influenced/modified in some way. But that probably doesn't meet the threshold for causation (at least it's not how we typically apply the word causation).

I think a reasonable standard for saying that AGW caused X is if X could not have occurred, or would have been dramatically less likely to occur, without AGW. In the case of extreme heatwaves, that standard has already been met. In the case of downpours, we haven't reached that threshold yet and possibly never will, but it is still possible to say that AGW is making downpours more likely.

I think this study demonstrates that downpours are increasing in the U.S. From what I know and from the arguments in the paper, I think that that trend is very likely mostly caused by AGW. I think you do raise a legitimate question about is this happening globally? If is that would strengthen the case that the increase in downpours is attributable to AGW. If the trend is not global, then perhaps it is in fact a regional/decadal thing.

But I think one thing you are missing and perhaps why you are being so skeptical of all this is that as the atmosphere warms water vapor increases pretty much immediately and proportionally. If you look at a graph of global temperature vs water vapor, they are almost perfectly correlated including all the ups and downs for ENSO. So given the atmosphere has warmed, this warming is attributed to human activity, and warming causes increased water vapor, the increase in water vapor is also attributable to AGW.

I agree the case would be made stronger by global data. But the increase in downpours matches theoretical expectations that have been around for decades. And conceptually it makes sense given the nearly linear long term rise on water vapor. And 60 years spans the length of most major natural cycles (PDO, AMO, ENSO etc.). Thus I do not feel too skeptical that the increase is due to AGW.

[tacoman25]

How could it not be? Every weather event, large and small, is taking place in a warmer, more moist environment. Where conditions are otherwise conducive, the higher mixing ratio of water vapor will enhance rainfall rate where total column precipitable water is greater,

The problem becomes when AGW alarmists cherry-pick certain catastrophic events and say: "See, this is what happens with AGW."

Most of the time, there is no direct or conclusive evidence that AGW led to specific events, but that doesn't slow the alarmists down. Heavy on the speculation, as long as it is a damaging/severe event that grabs the news headlines.

[gracetoyou]

Yes, but that's been my point all along. C02 is not "in control" as was stated by another poster. I do not believe that our climate is sensitive enough for a trace gas to sabotage natural factors. Can it or will it in the future have a greater impact? Possibly but there's still so much were learning. Like, studies showing the earth & oceans are doing quite well at absorbing C02, better than was expected...etc. Notice this paragraph:

Ballantyne, Tans and their colleagues saw no faster-than-expected rise, however. Their estimate showed that overall, oceans and natural ecosystems continue to pull about half of people’s carbon dioxide emissions out of the atmosphere. Since emissions of CO₂ have increased substantially since 1960, Ballantyne said, "Earth is taking up twice as much CO₂ today as it was 50 years ago."

The rest continues to accumulate in the atmosphere, where it is likely to accelerate global warming.

This new global analysis makes it clear that scientists do not yet understand well enough the processes by which ecosystems of the world are removing CO₂ from the atmosphere, or the relative importance of possible sinks: regrowing forests on different continents, for example, or changing absorption of carbon dioxide by various ocean regions.

http://www.noaanews....arbonstudy.html

I just think it seems way to early to jump on the C02 train just because we experienced accelerated warming from 1978-1998 during a +PDO which resulted in 4 of the strongest El Nino's ever recorded & extremely high solar activity. During the +PDO precipitation for the U.S. was way above normal & it was being blamed on AGW. PDO flips to it's negative cycle & U.S. starts getting dry & it's blamed on AGW. Higher precip during +PDO & drier conditions during -PDO is completely normal. I think it's illogical to immediately begin putting the finger on C02 & really minimizing the impacts of the natural factors. That's all I'm saying.

I agree with Coastal! I posted this earlier with no response. It's a classic example of the "unknown" that should throw out all the locked-in cockiness of the AGW side. I mean this is a study that shows C02 is absorbed quite well by oceans & earth...which was admitted UNEXPECTED. However, any dose of humility at the discovery is quickly thrown out the window with blazing arrogance at the prediction that this will not continue to be the case.

Also about temps: I've already posted a peer reviewed paper from 2011 by AGW supporting scientists admitting that there was no warming between 1998-2008.

http://wattsupwiththat.files.wordpress.com/2011/07/pnas-201102467.pdf

There has even been a slight decline. This is the BIG issue. It has to be! There's not a satisfactory answer to explain. If C02 is in control & PPM are at an all time high (significantly higher) since 1998 then why isn't our "sensitive climate" still responding with huge temp climbing that was seen from1978-1998? Enough talk about heatwaves, heavy precip events, droughts, etc. which have always occurred in history with great variability in frequency & intensity; too much so to blame confidently 100% on AGW. Global temperatures are the main issue & the lack of response to huge rises in C02 ppm the last 14 years with the temps has to be accounted for, rather than appealing to weather events.

Heck, guys I'm for green energy & a safer environment but not because of my concern for AGW. I also could careless about what Democrats or Republicans think on the issue. For me it's not political but just my great interest in weather that's lead to countless number of hours studying this just like many of you. I'm not saying anyone is 100% right or wrong but I'm totally blowing the whistle on the "locked-in, arrogant, we 100% know for sure" why any weather event is occurring. There's just still too much WE DO NOT KNOW to be so confident either way. That's all I'm saying & I think that's all Coastal & some others are saying. I'm not slamming any door shut on either side of the debate.

[CoastalWx]

I think there is some confusion because you're not distinguishing properly between individual events vs trends. There is a trend of increased heatwaves and of downpours. The trends can probably be attributed to AGW (definitely for the increased trend of heatwaves). As for individual events, it can get much more complicated because you get into basically almost butterfly effect questions. All events are changed/influenced/modified in some way. But that probably doesn't meet the threshold for causation (at least it's not how we typically apply the word causation).

I think a reasonable standard for saying that AGW caused X is if X could not have occurred, or would have been dramatically less likely to occur, without AGW. In the case of extreme heatwaves, that standard has already been met. In the case of downpours, we haven't reached that threshold yet and possibly never will, but it is still possible to say that AGW is making downpours more likely.

I think this study demonstrates that downpours are increasing in the U.S. From what I know and from the arguments in the paper, I think that that trend is very likely mostly caused by AGW. I think you do raise a legitimate question about is this happening globally? If is that would strengthen the case that the increase in downpours is attributable to AGW. If the trend is not global, then perhaps it is in fact a regional/decadal thing.

But I think one thing you are missing and perhaps why you are being so skeptical of all this is that as the atmosphere warms water vapor increases pretty much immediately and proportionally. If you look at a graph of global temperature vs water vapor, they are almost perfectly correlated including all the ups and downs for ENSO. So given the atmosphere has warmed, this warming is attributed to human activity, and warming causes increased water vapor, the increase in water vapor is also attributable to AGW.

I agree the case would be made stronger by global data. But the increase in downpours matches theoretical expectations that have been around for decades. And conceptually it makes sense given the nearly linear long term rise on water vapor. And 60 years spans the length of most major natural cycles (PDO, AMO, ENSO etc.). Thus I do not feel too skeptical that the increase is due to AGW.

Yes it does span the cycles, but I'm not sure we can gauge an accurate trend if it doesn't even capture 2 cycles of both + and - decadal cycles. I don't think we're far off in our arguments..it comes down to how this article is put forth and the cherry picking they used to prove there points. March 2010 had great blocking, but that was a product of a perfect combo of ENSO,QBO, and low solar. So again, to use March 2010 for BOS as an example to prove their point for the US precip increase just does not see correct at all. They did this study just for the US, but it would be much more useful to do this study with viable stations across the globe. This may be a tough task since international data can be sketchy. I know, I used to QC this data every day. But, it would help prove their point and not just deal with the US where cycles may have more of a say in the precip anomalies since this is a much smaller geographical area. To me, their 60 years of data imo, isn't quite enough to prove that yes we are doing this to ourselves...especially when it is US concentrated.

Even the recent heat wave...this imo has more to do with the feedback from the serious drought the Plains and west had thanks to the AK vortex aided by MJO convection..than by climate change. When the winter is dry and March (which is supposed to have ridiculously high soil moisture) comes in parched....it's off to the races as the sun angle increases. Soil moisture in Spring is huge as trees have no leaves and all the sun's energy goes into heating the soil. Some of it possibly may be explained by climate change, but the US was in another world compared to the rest of the globe. Similarities can be found from 1988 which continues to be the costliest ag disaster around...and also the events of the 30s and 40s which had similar patterns. If in the next 30 years we keep seeing these events...well than we know we may have a problem bigger than it currently is. So while Climate Change may be having somewhat of a say...I just don't think we can accurately say that we are causing certain events moreso than natural variability or causes. I understand the trend of recent heatwaves, but it's the last 3 years that have really stirred this conversation. Lets see how this goes in the next 10-20 years. I doubt this absurd heat we've had recently continues.

[WeatherRusty]

The problem becomes when AGW alarmists cherry-pick certain catastrophic events and say: "See, this is what happens with AGW."

Most of the time, there is no direct or conclusive evidence that AGW led to specific events, but that doesn't slow the alarmists down. Heavy on the speculation, as long as it is a damaging/severe event that grabs the news headlines.

Do you mean the 3 sigma standard deviation type events? Maybe a clustering of 100-500 year type events?

[tacoman25]

Do you mean the 3 sigma standard deviation type events? Maybe a clustering of 100-500 year type events?

I mean Hurricane Katrina, the devastating tornado outbreaks last year, the huge winter storms many places saw in 2009-10 and 2010-11, or random floods like Duluth and Nashville in recent years.

None of these events could be directly blamed on AGW or even necessarily connected from a purely scientific standpoint, but many alarmists were quick to try to make some sort of connection. Many feel that the public should be ALARMED about catastrophic AGW, and therefore what better way to bring attention to that viewpoint than by associating catastrophic events with AGW.

[skierinvermont]

I mean Hurricane Katrina, the devastating tornado outbreaks last year, the huge winter storms many places saw in 2009-10 and 2010-11, or random floods like Duluth and Nashville in recent years.

None of these events could be directly blamed on AGW or even necessarily connected from a purely scientific standpoint, but many alarmists were quick to try to make some sort of connection. Many feel that the public should be ALARMED about catastrophic AGW, and therefore what better way to bring attention to that viewpoint than by associating catastrophic events with AGW.

The suggestions about Katrina and the tornadoes was from fringe media elements. You're basically setting up a strawman.

It is fair to point out that the extreme floods like Duluth and Nashville are the types of events that have been increasing in frequency and will continue to do so.

[tacoman25]

The suggestions about Katrina and the tornadoes was from fringe media elements. You're basically setting up a strawman.

It is fair to point out that the extreme floods like Duluth and Nashville are the types of events that have been increasing in frequency and will continue to do so.

Disagree. I recall reading several statements/articles that at least inferred AGW played a role in Katrina and the tornadoes, or even if they didn't directly blame AGW, made a strong association by saying that such events would become more and more common because of AGW.

As far as the floods go, if AGW can be blamed for a 10% increase in precipitation in major precip events (a rather tenuous assertion based on the evidence presented in this study, I believe, but we'll go with it), a 10% decrease for those events still would have easily resulted in a major flood event.

[ben4vols]

The suggestions about Katrina and the tornadoes was from fringe media elements. You're basically setting up a strawman.

It is fair to point out that the extreme floods like Duluth and Nashville are the types of events that have been increasing in frequency and will continue to do so.

There were other factors that played into the Nashville flood. One being our system of dams around the middle-TN area has come under some scrutiny for their role in the flooding.

[tacoman25]

The increase in extreme precipitation in this study follows from previous work in this field along with the

information on the NCDC site. The June record flooding in Minnesota occurred against a backdrop

of increasing precipitation extremes in that region. There really is nothing surprising about that.

The odds of such extreme events rise in a warming climate.

http://www.ncdc.noaa.gov/extremes/cei/

Again, please show how a 10% increase in precipitation amounts (assuming the number in this study is accurate) is responsible for those events. Maybe 10% responsible? Meaning that the vast majority of the event was due to factors other than AGW. Fixating on AGW when it comes to these events is kind of silly, imo.

You hear this "odds of extreme events rises in a warming climate" mantra over and over, but the tendency to automatically point to AGW anytime something "extreme" happens is misguided, I believe.

[CoastalWx]

Well at least we got a discussion going...this is how the science is supposed to advance, right?

[PhillipS]

Well at least we got a discussion going...this is how the science is supposed to advance, right?

Um, no, not really. You were given links to a wealth of peer-reviewed research - but instead of reading it and learning something you kept posting your same unsupported opinions over and over and over.

At best your comprehension level is finally up to where most of us were weeks ago. Congratulations!

[FPizz]

Bad storm = global warming. "Typical" storm = weather.

[The_Global_Warmer]

How can one admit water vapor has increased due to the Earth Warming, which humans are responsible for and then not be able to admit that AGW is always effecting the weather, every pattern, every day, because the Earth's climate today is warmer than before, it has new rules, new rules equal new results.

But the disconnect is Coastalwx believes natural cycles are the predominate cause of the warming. So out of 100% warming I assume he believes 75% or more is natural factors. That is the point of disconnect, the literature and science says he is wrong but he is allowed to believe what he wants.

But now the data does not complete his line of logic. So the data is either incorrect or incorrectly applied, in this case maybe both but the data can be correctly applied to natural forcings? I am not sure.

But the conversation isn't go far when folks are standing on AGW is not the main driving force behind the incredible jumps in energy balance the Earth is making.

If your going to go against the evidence that is currently accepted as reality or our best guess, then bring some compelling evidence to argue it.

[rygar]

Not so long ago compelling evidence suggested the earth was flat.

Part of Science is also understanding the limitations of a data set.

[toronto blizzard]

How can one admit water vapor has increased due to the Earth Warming, which humans are responsible for and then not be able to admit that AGW is always effecting the weather, every pattern, every day, because the Earth's climate today is warmer than before, it has new rules, new rules equal new results.

But the disconnect is Coastalwx believes natural cycles are the predominate cause of the warming. So out of 100% warming I assume he believes 75% or more is natural factors. That is the point of disconnect, the literature and science says he is wrong but he is allowed to believe what he wants.

But now the data does not complete his line of logic. So the data is either incorrect or incorrectly applied, in this case maybe both but the data can be correctly applied to natural forcings? I am not sure.

But the conversation isn't go far when folks are standing on AGW is not the main driving force behind the incredible jumps in energy balance the Earth is making.

If your going to go against the evidence that is currently accepted as reality or our best guess, then bring some compelling evidence to argue it.

Show me the science that says CoastalWX is wrong

[toronto blizzard]

Um, no, not really. You were given links to a wealth of peer-reviewed research - but instead of reading it and learning something you kept posting your same unsupported opinions over and over and over.

At best your comprehension level is finally up to where most of us were weeks ago. Congratulations!

You just don't want to accept an opinion that you think is wrong. Why can't you believe that at least some of the warming is caused by natural factors?

[toronto blizzard]

The increase in extreme precipitation in this study follows from previous work in this field along with the

information on the NCDC site. The June record flooding in Minnesota occurred against a backdrop

of increasing precipitation extremes in that region. There really is nothing surprising about that.

The odds of such extreme events rise in a warming climate.

http://www.ncdc.noaa.gov/extremes/cei/

What makes you certain that the June record flooding in Minnesota is absolutely caused by AGW?

[The_Global_Warmer]

Not so long ago compelling evidence suggested the earth was flat.

Part of Science is also understanding the limitations of a data set.

I would love to see that kind of evidence put up against the data we have accumulated on AGW.

[toronto blizzard]

I don't think CC has anything to do with creating heavier precip

[TerryM]

I don't think CC has anything to do with creating heavier precip

Thanks so much for clearing that up for the rest of us.

Terry

[Jonger]

Those are your words. It's probably better to look at it like this:

http://climatecrocks...rom-the-future/

As I said in my postearly Thursday, my read is that this type of event “fits” in the overall picture of Minnesota’s changing climate. What we can’t credibly say in my opinion is that this entire event was “caused” by climate change. What we can credibly say is the extreme rainfall events are increasing in frequency in Minnesota, and that climate changes favoring a warmer wetter atmosphere may have enhanced or “juiced” rainfall totals in the flood.

We’ve always had active warm fronts that have spawned MCS and heavy nighttime rains in Minnesota. The meteorological set up would have occurred anyway. But CC may have “enhanced” the Duluth flood event.

Now the real question is, did a warmer & wetter atmosphere “juice” this particular event to produce more rainfall than would have occurred without CC? That’s the real question…and how do you quantify how much “extra” rain fell as a result of a warmer/wetter climate?

We know, and I have blogged/discussed on MPR that 3″+ rainfall events have doubled in frequency since about 1960. According to a report from climatenexus.org there has been a 31% increase in extreme rainfall events in the Midwest since 1958.

Have you considered that the pre-1960 stations might have been drier than normal?

I HATE using personal recollections in climate discussion, but I have a different memories of late 1980's through today.

Just about everyone I speak with remembers more summer evening downpours and storms, we just aren't getting that anymore. This was obviously before easy access to radar, but the current summer weather is noticeably less exciting then years back for my local.

Again, just personal recollection.

[Jonger]

Thanks so much for clearing that up for the rest of us.

Terry

Ah, a little Canadian on Canadian battle royale.

[donsutherland1]

Why can't you believe that at least some of the warming is caused by natural factors?

First, as a disclaimer, no one is suggesting that all recent weather events (heat, drought, storminess, etc.) are 100% explained by AGW.

There are natural forcings and anthropogenic forcings. Natural forcings include solar activity, volcanic activity, and orbital fluctuations. Anthropogenic forcings include, but are not limited to CO2 emissions that are driving increasing atmospheric concentration of CO2. The radiative forcing associated with that growing atmospheric CO2 is increasing relative to the natural forcings, as one would expect given that those forcings have remained relatively stable while atmospheric CO2 has been increasing. Today CO2 is the dominant forcing.

The scientific literature reveals that since the mid-20th century, natural forcings implied a stable or slow decline in the global temperautre. However, that's not what happened. Instead, the global temperature increased and especially dramatically as the 21st century commenced. When CO2 is added into the mix, the recent climate record can be replicated. Even in the Arctic where a millennial scale decrease in temperatures had been underway due to falling summer solar insolation associated with orbital forcings, that trend ended abruptly in the 20th century and fairly rapid warming has occurred there. On a relatively unchanged course with respect to CO2 emissions, CO2's influence will continue to grow relative to the natural forcings.

Aside from the forcings, there are the oceanic cycles. Those cycles include the AMO, PDO, and ENSO. Those cycles continue to play out. As the PDO warmed during the 1980s and 1990s before reversing around 2007, that cycle amplified the warming associated with the growing anthropogenic forcing. Now the PDO is negative. Nevertheless, global temperatures remain well above their 20th century (NCDC climatic base) or 1951-80 (GISS climatic base) reference points. The oceanic cycles will continue to play out, but in the context of a warming global climate. The PDO-/AMO+ setup is linked to U.S. drought. Not surprisingly, a drought is playing out, as it did during the 1950s. However, unlike the 1950s, the background warming has contributed to a similar scale drought's producing extreme heat comparable with the more severe Dust Bowl droughts. So yes, natural cycles are playing a role, but they are doing so within the broader framework of a warming climate.

Finally, there are synoptic patterns. Those can be influenced by such events as the drought via feedbacks. However, even as the synoptic patterns continue to play out as they have in the past, there's a big difference from the past (20th century). Areas of extreme warmth (2- and 3-sigma above normal) have increased rather dramatically. Why are the same synoptic patterns as have occurred in the past suddenly leading to outcomes conducive to more widespread and severe heat all things being equal? Again, it is the background warming that is playing a role.

Forcings, oceanic cycles, and synoptic patterns (along with feedbacks) are not independent mutually exclusive factors. Instead, they play out together. Synoptic patterns occur in the broader context of the oceanic cycles. The synoptic patterns and oceanic cycles play out in the broader context of the forcings (natural and anthropogenic).

[PhillipS]

You just don't want to accept an opinion that you think is wrong. Why can't you believe that at least some of the warming is caused by natural factors?

I have accepted all along that some of the warming may be caused by natural variation. But I have also accepted all along that the quasi-periodic fluctuations of natural variation can't explain much of the long-term warming that has been observed so the logical cause of most global warming is mankind.. I have also studied and understand fairly well the physics of the GHE and evidence that our burning gigatons of fossil fuels is altering the climate.

Do you accept that what climate change natural variation doesn't explain is probably due to man's activities? If not, how do you explain it? Mystical unknown forces? Astrological alignment of the planets, perhaps? Extraterrestrials?

And your berating me for not accepting some clown's opinion is just silly. Why should any rational person accept an unsupported opinion that goes against the body of peer-reviewed research?

[ben4vols]

I have accepted all along that some of the warming may be caused by natural variation. But I have also accepted all along that the quasi-periodic fluctuations of natural variation can't explain much of the long-term warming that has been observed so the logical cause of most global warming is mankind.. I have also studied and understand fairly well the physics of the GHE and evidence that our burning gigatons of fossil fuels is altering the climate.

Between natural variations and data adjustments, that just about covers it. "And I must admit that those adjustments constituting virtually all of the warming signal in the last 40 years is disconcerting. When “global warming” only shows up after the data are adjusted, one can understand why so many people are suspicious of the adjustments." - Roy Spencer

[CoastalWx]

Um, no, not really. You were given links to a wealth of peer-reviewed research - but instead of reading it and learning something you kept posting your same unsupported opinions over and over and over.

At best your comprehension level is finally up to where most of us were weeks ago. Congratulations!

Well congrats on derailing it and acting clueless once again.

[CoastalWx]

I have accepted all along that some of the warming may be caused by natural variation. But I have also accepted all along that the quasi-periodic fluctuations of natural variation can't explain much of the long-term warming that has been observed so the logical cause of most global warming is mankind.. I have also studied and understand fairly well the physics of the GHE and evidence that our burning gigatons of fossil fuels is altering the climate.

Do you accept that what climate change natural variation doesn't explain is probably due to man's activities? If not, how do you explain it? Mystical unknown forces? Astrological alignment of the planets, perhaps? Extraterrestrials?

And your berating me for not accepting some clown's opinion is just silly. Why should any rational person accept an unsupported opinion that goes against the body of peer-reviewed research?

Thanks for making our point. You show a few brain cells after all.

[CoastalWx]

How can one admit water vapor has increased due to the Earth Warming, which humans are responsible for and then not be able to admit that AGW is always effecting the weather, every pattern, every day, because the Earth's climate today is warmer than before, it has new rules, new rules equal new results.

But the disconnect is Coastalwx believes natural cycles are the predominate cause of the warming. So out of 100% warming I assume he believes 75% or more is natural factors. That is the point of disconnect, the literature and science says he is wrong but he is allowed to believe what he wants.

But now the data does not complete his line of logic. So the data is either incorrect or incorrectly applied, in this case maybe both but the data can be correctly applied to natural forcings? I am not sure.

But the conversation isn't go far when folks are standing on AGW is not the main driving force behind the incredible jumps in energy balance the Earth is making.

If your going to go against the evidence that is currently accepted as reality or our best guess, then bring some compelling evidence to argue it.

Well than you would have to include ORH and some other mets too. The point of this whole conversation was the fact that the article simply is not correct in pointing out how individual events can be blamed on AGW. It has nothing to do with me or anyone else denying warming. It's clear the Earth has warmed, but most of us who question some of the posts here believe natural variations may explain at least part of the warming. How much..who knows, but I don't think anyone can assign a value. Maybe it's only 60/40...we simply don't know and the Earth is much more intricate then some computer spitting out a solution.

[donsutherland1]

And I must admit that those adjustments constituting virtually all of the warming signal in the last 40 years is disconcerting.

If "virtually all" of the observed warming were the result of data adjustments, then growing seasons, plant hardiness zones, bird wintering ranges, lake ice duration would all be close to stable. Instead, nature's response is consistent with warming:

1. Growing seasons are lengthening: http://epa.gov/climatechange/science/indicators/society-eco/growing-season.html

2. Plant hardiness zones are shifting north: http://epa.gov/climatechange/science/indicators/society-eco/plant-zones.html

3. Bird wintering ranges are shifting north: http://epa.gov/climatechange/science/indicators/society-eco/bird-ranges.html

4. Lake ice duration is growing shorter, lakes are freezing later and thawing earlier: http://epa.gov/climatechange/science/indicators/snow-ice/lake-ice.html

The warming is real, not imaginary.