Another skeptic converts

[Cheeznado]

http://www.nytimes.c...&pagewanted=all

[donsutherland1]

http://www.nytimes.c...&pagewanted=all

Some key points:

Just as important, our record is long enough that we could search for the fingerprint of solar variability, based on the historical record of sunspots. That fingerprint is absent. Although the I.P.C.C. allowed for the possibility that variations in sunlight could have ended the “Little Ice Age,” a period of cooling from the 14th century to about 1850, our data argues strongly that the temperature rise of the past 250 years cannot be attributed to solar changes. This conclusion is, in retrospect, not too surprising; we’ve learned from satellite measurements that solar activity changes the brightness of the sun very little.

How definite is the attribution to humans? The carbon dioxide curve gives a better match than anything else we’ve tried. Its magnitude is consistent with the calculated greenhouse effect — extra warming from trapped heat radiation. These facts don’t prove causality and they shouldn’t end skepticism, but they raise the bar: to be considered seriously, an alternative explanation must match the data at least as well as carbon dioxide does. Adding methane, a second greenhouse gas, to our analysis doesn’t change the results. Moreover, our analysis does not depend on large, complex global climate models, the huge computer programs that are notorious for their hidden assumptions and adjustable parameters. Our result is based simply on the close agreement between the shape of the observed temperature rise and the known greenhouse gas increase.

[Jonger]

It’s a scientist’s duty to be properly skeptical. I still find that much, if not most, of what is attributed to climate change is speculative, exaggerated or just plain wrong. I’ve analyzed some of the most alarmist claims, and my skepticism about them hasn’t changed.

Hurricane Katrina cannot be attributed to global warming. The number of hurricanes hitting the United States has been going down, not up; likewise for intense tornadoes. Polar bears aren’t dying from receding ice, and the Himalayan glaciers aren’t going to melt by 2035. And it’s possible that we are currently no warmer than we were a thousand years ago, during the “Medieval Warm Period” or “Medieval Optimum,” an interval of warm conditions known from historical records and indirect evidence like tree rings. And the recent warm spell in the United States happens to be more than offset by cooling elsewhere in the world, so its link to “global” warming is weaker than tenuous.

[Cheeznado]

However, the consensus is growing to the point of pretty much FACT: AGW is real. We are not cooling. period.

[andyhb]

It’s a scientist’s duty to be properly skeptical. I still find that much, if not most, of what is attributed to climate change is speculative, exaggerated or just plain wrong. I’ve analyzed some of the most alarmist claims, and my skepticism about them hasn’t changed.

Hurricane Katrina cannot be attributed to global warming. The number of hurricanes hitting the United States has been going down, not up; likewise for intense tornadoes. Polar bears aren’t dying from receding ice, and the Himalayan glaciers aren’t going to melt by 2035. And it’s possible that we are currently no warmer than we were a thousand years ago, during the “Medieval Warm Period” or “Medieval Optimum,” an interval of warm conditions known from historical records and indirect evidence like tree rings. And the recent warm spell in the United States happens to be more than offset by cooling elsewhere in the world, so its link to “global” warming is weaker than tenuous.

Not exactly (obviously the spikes can be mostly attributed to major outbreaks). This year will in all likelihood be a major contrast to last year, barring some serious late Summer/Fall activity. That said, it appears there was a higher frequency of "spiking" years from the 50's to the 70's, but who knows if the apparent decrease is due to climate change, global warming, a changed tornado rating system (Fujita vs. Enhanced), a lack of synoptic systems coming together with such explosive nature as to induce conditions supportive of intense/violent tornadoes (i.e, 4/27/11, 4/3/74, 4/11/65, 3/21/52), dumb luck or some other factor.

[ORH_wxman]

Not exactly (obviously the spikes can be mostly attributed to major outbreaks). This year will in all likelihood be a major contrast to last year, barring some serious late Summer/Fall activity. That said, it appears there was a higher frequency of "spiking" years from the 50's to the 70's, but who knows if the apparent decrease is due to climate change, global warming, a changed tornado rating system (Fujita vs. Enhanced), a lack of synoptic systems coming together with such explosive nature as to induce conditions supportive of intense/violent tornadoes (i.e, 4/27/11, 4/3/74, 4/11/65, 3/21/52), dumb luck or some other factor.

There might be reasons for the decrease...but the decrease currently exists in violent tornadoes. There is no evidence global warming would increase tornadoes or their strength.

[Jonger]

Not exactly (obviously the spikes can be mostly attributed to major outbreaks). This year will in all likelihood be a major contrast to last year, barring some serious late Summer/Fall activity. That said, it appears there was a higher frequency of "spiking" years from the 50's to the 70's, but who knows if the apparent decrease is due to climate change, global warming, a changed tornado rating system (Fujita vs. Enhanced), a lack of synoptic systems coming together with such explosive nature as to induce conditions supportive of intense/violent tornadoes (i.e, 4/27/11, 4/3/74, 4/11/65, 3/21/52), dumb luck or some other factor.

There is no correlation to climate change with tornados, hurricanes or derechos (Yup, Dr. Masters went there). We have a warmer arctic and that is pretty much the scope of the issue at hand.

[Ellinwood]

Not exactly (obviously the spikes can be mostly attributed to major outbreaks). This year will in all likelihood be a major contrast to last year, barring some serious late Summer/Fall activity. That said, it appears there was a higher frequency of "spiking" years from the 50's to the 70's, but who knows if the apparent decrease is due to climate change, global warming, a changed tornado rating system (Fujita vs. Enhanced), a lack of synoptic systems coming together with such explosive nature as to induce conditions supportive of intense/violent tornadoes (i.e, 4/27/11, 4/3/74, 4/11/65, 3/21/52), dumb luck or some other factor.

The change in the tornado rating system did not change the number of intense/violent tornadoes. The Enhanced Fujita scale changed the wind speeds derived from the tornado damage. There wasn't any real change to how tornadoes get rated on the scale from 0-5.

[QVectorman]

He is a flip flopper anyways

Muller 2003: CO2 "the greatest pollutant of human history. It is likely to have severe and detrimental effects"

http://www.technologyreview.com/news/402357/medieval-global-warming/2/

[TerryM]

He is a flip flopper anyways

Muller 2003: CO2 "the greatest pollutant of human history. It is likely to have severe and detrimental effects"

http://www.technolog...obal-warming/2/

Ad hominem is really all the deniers have left.

[Isotherm]

Is this thread supposed to prove anything? One conversion story, congrats.

I can post this link in response, regarding the tons of NASA scientists who disagree with/aren't happy with the catastrophic claims being made by Hansen et al:

http://www.powerline...ng-hysteria.php

Mine doesn't prove anything either, but if you're going to post about people converting to "AGW" believers, then the opposite should be posted as well, in the interest of objectivity.

[donsutherland1]

Dr. Muller's key point is that "the carbon dioxide curve gives a better match than anything else we’ve tried."

His key challenge is that, "...to be considered seriously, an alternative explanation must match the data at least as well as carbon dioxide does."

That CO2 largely explains the observed warming is his conclusion and that the warming is consistent with the radiative forcings associated with CO2. His challenge is also the logical one. Those who argue for an alternative need to find some factor or factors that explain the observed warming at least as well as CO2 does. Solar has been irrelevant. The oceanic cycles don't explain things as well either.

Here are the 30-year trends:

[WeatherRusty]

What do we know with a high degree of certainty?

This is what I think in a nutshell.

The Earth's climate is warming and has been for more than a century.

We can explain the warming as due to a combination of human introduced factors (mostly increasing CO2), a bit of solar variability and a general reduction in volcanic activity.

As the climate warms, atmospheric water vapor content increases as saturation vapor pressure grows exponentially.

-------------------

As most people here are well versed in what makes the weather tick, how do those simple facts play into how we might expect the general circulation to respond? What reasonable assumptions can be made?

I'll name a few:

Reduction in global ice mass.

Rising sea levels.

Since there is more water vapor in the air, what goes up must come down, meaning increased precipitation.

Higher values for convective available potential energy (CAPE). What happens to lapse rates? Do they change at all?

Why do we expect more flooding? Stronger droughts? Longer duration heat waves. Stronger but fewer hurricanes? Stronger more prevalent mesoscale convective complexes? etc.

[PhillipS]

Is this thread supposed to prove anything? One conversion story, congrats.

I can post this link in response, regarding the tons of NASA scientists who disagree with/aren't happy with the catastrophic claims being made by Hansen et al:

http://www.powerline...ng-hysteria.php

Mine doesn't prove anything either, but if you're going to post about people converting to "AGW" believers, then the opposite should be posted as well, in the interest of objectivity.

Since the NASA letter you linked to was from a number of retired employees, not scientists and certainly not physicists or climatologists, that's somewhat of an apples to oranges comparison. Now, if you can provide a link to a NASA climatologist who has changed his or her mind about AGW I would love to read that.

I agree that in the grand scheme of things Dr Muller's change of heart means little or nothing. The reality of AGW is corroborated by data, not by rhetoric, opinions or personalities.

[WeatherRusty]

Is this thread supposed to prove anything? One conversion story, congrats.

I can post this link in response, regarding the tons of NASA scientists who disagree with/aren't happy with the catastrophic claims being made by Hansen et al:

http://www.powerline...ng-hysteria.php

Mine doesn't prove anything either, but if you're going to post about people converting to "AGW" believers, then the opposite should be posted as well, in the interest of objectivity.

Who cares what a bunch of scientists think if they are not involved in climate science?

That article reeks of political and ideological overtones. NO science.

[salbers]

Since there is more water vapor in the air, what goes up must come down, meaning increased precipitation.

Higher values for convective available potential energy (CAPE). What happens to lapse rates? Do they change at all?

Why do we expect more flooding? Stronger droughts? Longer duration heat waves. Stronger but fewer hurricanes? Stronger more prevalent mesoscale convective complexes? etc.

Perhaps average rainfall wouldn't change so much, being driven more by solar energy input (and attendant energy conversion efficiency) rather than the increasing water vapor content.

[donsutherland1]

And in terms of Muller's pointing out the "absence" of a "solar fingerprint," here is the match of global temperatures with solar activity (30-year smoothing to take out the noise of interannual variability).

[QVectorman]

Yup over the past 33 years it matches up perfectly. And it also has matched up well for the past 450,000 years

[WeatherRusty]

Yup over the past 33 years it matches up perfectly. And it also has matched up well for the past 450,000 years

What you notice in the graphic is CO2 delayed about 800 years since that is approximately the time required to over turn the oceans. The overturning brings to the surface CO2 rich water from the depths where the newly warmer water outgases the excess CO2 out of solution. Over the course of the glacial cycles atmospheric CO2 waxes and wanes between 180ppm and 280ppm during full glacial and interglacials respectively. This is CO2 acting to amplify the Milankovitch induced initial change in conditions. CO2 is acting as feedback in this instance.

[donsutherland1]

Apparently, JB has weighed in on Dr. Muller's op-ed. Setting aside the commentary that is largely irrelevant, JB's major argument is:

Muller does not understand the implications that the oceans and TSI would easily explain the rises.

Let's have a look at the smoothed 30-year moving averages.

Independent Variables: PDO, AMO, and Solar:

Independent Variable: CO2:

Which chart has a closer fit to the observed global land and ocean temperature anomalies?

FWIW, if data for the first six months of 2012 were included, one would find continuing divergence on the first chart and a continued extremely close fit on the second one.

[toronto blizzard]

Don I'm sorry but those graphs that you posted that show the correlation between CO 2 and temp just don't seem right to me

[donsutherland1]

Don I'm sorry but those graphs that you posted that show the correlation between CO 2 and temp just don't seem right to me

As Excel files can't be attached, I'll be happy to e-mail you a copy of the data file.

[The_Global_Warmer]

Don I'm sorry but those graphs that you posted that show the correlation between CO 2 and temp just don't seem right to me

By all means share with us what you find wrong with it? I am sure Don will explain the methodology.

[donsutherland1]

The Muller paper has now been posted. It can be found at: http://berkeleyearth.org/pdf/results-paper-july-8.pdf

[Entropy]

The Muller paper has now been posted. It can be found at: http://berkeleyearth...aper-july-8.pdf

Thanks for the link. I, for one, am not too surprised by the findings of the BEST team. The warming signal seems pretty robust, based on the data I've seen.

[Entropy]

Our analysis approach differed from that of the previous groups in several ways. Rather than adjust (“homogenize”) individual records for known and presumed discontinuities (e.g. from instrument changes and station moves), we split the records at such points, creating essentially two records from one. This procedure was completely automated to reduce human bias; we call this approach the scalpel. The detection of such breakpoints followed procedures similar to those used by existing groups, but the traditional adjustment step was omitted in favor of simply dividing the time series into two pieces at any apparent breakpoints. We also split records when there was a gap in record continuity greater than 1 year in duration, and at times when changes in station location or time of observation were documented.

This approach makes a lot of sense to me. Eliminates the need to worry about adjusting for site changes and instrument changes by treating each such change as a completely new station. I'd be interested to see what this approach would yield for the U.S. temperature record, especially given some of the recent criticism of the adjustments for the switch in time of observation, the switch to MMTS, and urban heat island effects. I've often wondered if some of the skepticism towards climate change isn't due to the NWS policy of grafting disparate sites together to create an "official" temperature record for most major cities. A lot of the older records were taken at downtown locations, often on rooftops, before moving to ground-based airport sites well outside the city and often at higher elevation (although with urban sprawl, urbanization has rapidly encroached on many of the busier metropolitan airports). Sites that have significant changes in location generally aren't used in the USHCN data set, but there are some exceptions. USHCN uses standard UHI adjustments to correct for site changes by regression using nearby sites. The BEST approach would completely eliminate the need to rely on these adjustments and also enable more data to be used in the overall analysis.

[andyhb]

The change in the tornado rating system did not change the number of intense/violent tornadoes. The Enhanced Fujita scale changed the wind speeds derived from the tornado damage. There wasn't any real change to how tornadoes get rated on the scale from 0-5.

I meant more in the sense of the science of rating tornadoes has become much more focussed since Fujita first introduced the scale, like for example, some say that several of the violent tornadoes in the 4/3/74 outbreak would not be rated as high currently, due to a greater knowledge of how tornadic winds affect buildings.

[andyhb]

There might be reasons for the decrease...but the decrease currently exists in violent tornadoes. There is no evidence global warming would increase tornadoes or their strength.

Whoever has said that tornado numbers have increased is forgetting the fact that tornado detection is lightyears ahead of what it used to be, I'm sure there have been years with more tornadoes than 2004/2008/2011, just no one was there to report/archive them.

[Ellinwood]

I meant more in the sense of the science of rating tornadoes has become much more focussed since Fujita first introduced the scale, like for example, some say that several of the violent tornadoes in the 4/3/74 outbreak would not be rated as high currently, due to a greater knowledge of how tornadic winds affect buildings.

That's not what you said at all. Adjusting a couple of tornadoes here and there each year would not be enough to change the overall trend as you suggested:

"who knows if the apparent decrease is due to climate change, global warming, a changed tornado rating system."

Even if there were discrepancies between F/EF 3-5 tornadoes, that still wouldn't affect the overall intense/violent tornado count so long as they aren't weakened below F/EF 3 status.

Whoever has said that tornado numbers have increased is forgetting the fact that tornado detection is lightyears ahead of what it used to be, I'm sure there have been years with more tornadoes than 2004/2008/2011, just no one was there to report/archive them.

While it is true that the count for weaker tornadoes (F/EF 0-1) have trended higher due to better reporting and recognition, there has been no such notable inflation to the count for intense/violent tornadoes since their effects are much more apparent and easier to recognize.

[andyhb]

While it is true that the count for weaker tornadoes (F/EF 0-1) have trended higher due to better reporting and recognition, there has been no such notable inflation to the count for intense/violent tornadoes since their effects are much more apparent and easier to recognize.

I wasn't referring to just EF3+ tornadoes in that statement, simply the overall number of them per year.