Tamino links to a “Crock of the Week” video where the Narrator reads a script in what I think is an “adjective” tone of voice:
I’ll let you decide pick your adjetive.
The script seems to have been written by Bill McKibben and, particularly narrated with a certain tone of voice seems to suggest that one must connect recent tornado outbreaks with climate change. Portions of McKibben’s article were quoted and discussed by John Neilsen-Gammon.
In response to the article, JNG began:
First off, they are connected, through this past year’s moderate-to-strong La Nina.
So, yeah. The events are connected.
JGN continues– noting that, on the one hand, the weather might be affected by climate change, but on the other hand, Harold Brooks the world’s fore most tornado expert evidently thinks tornadoes are just as likely to weaken as strengthen as a result of climate change.
Needless to say, when I listened to the sarcastic sounding narrative, I remembered this Brooke’s quote
“I get really worried when people oversell the case.”
Might I suggest that video is overselling. Just a tad?
Anyone who tries to actually argue that tornadoes will become more frequent due to climate change is doing more than overselling, they are arguing against empirical evidence to the contrary: namely that, as the world and the US warmed in the last fifty years, the number of strong to violent tornadoes in the US declined:
http://www.ncdc.noaa.gov/img/climate/research/tornado/tornadotrend.jpg
“connect recent tornado outbreaks with climate change”
Has anyone compiled a list of places where the climate has changed?
Andrew
One really funny aspect to this debate is how Eli the weird wabbit tries (poorly) to trap JNG in the comment section to JNG’s analysis. On his own website (bunnysite?), Eli claims that the tell to the question being a “trap” was the way he phrased the question, saying: “Now, if Eli has taught the bunnies anything, it is to look at awkwardly put questions with a jaundiced eye.”
This is truly hilarious (though I doubt Eli appreciates why). When have we ever seen the wanton wabbit phrase anything (anything at all) in a way that wasn’t awkward?
Judith Curry contrasted Roy Spencer’s use of actual data with Bill McKibben’s op-ed.
http://judithcurry.com/2011/05/25/more-tornado-madness/
One of Spencer’s posts showing declining strong tornadoes and warming temperatures:
http://www.drroyspencer.com/2011/05/todays-tornado-outlook-high-risk-of-global-warming-hype/
brid
Maybe Eli thinks all his phrases are traps.
Roger Pielke Jr. had a post linking to an Australian climate scientist’s study of this year’s flooding down under; conclusion – the strong La Nina did it. The graph going back to 1900 shows the 6 rainyest years were strong La Nina years – that is, high SOI on the graph.
http://rogerpielkejr.blogspot.com/2011/04/neville-nicholls-on-australias-extreme.html
Lucia,
I watched the video and had a similar reaction to yours. Latching onto recent tornadoes seems one of the weakest cases you can make, given the lack of a trend on strong tornadoes over recent years and the large uncertainty in wind shear vs. humidity effects on tornado formation.
To put it more succinctly, both sides in the debate often need to be reminded that a single data point does not make a trend.
It really is just weather. In August 2010 Joe Bastardi (he and partner Joe D’Aleo follow ENSO, PDO, etc.) made a winter forecast in which he said “This may be a great winter for building the Pacific Northwest and Canada snowpack, which is opposite of last winter,” And, “Southern California and portions of the Southwest could be threatened by a severe drought and high danger for wildfires..”
http://snowlover123.blogspot.com/2010/08/accuweathercoms-joe-bastardi-on-2010.html
Oregon’s Mt. Bachelor ski area closed on May 31, and their website says “Mt Bachelor recorded 665 inches of snow this La Nina season, besting the previous record of 606 inches set during the similar La Nina winter of 1998-1999.”
http://www.mtbachelor.com/winter/mountain/snow_report
Unless one believes that climate change will increase the frequency/intensity of La Nina (I’ve heard claims of more/stronger El Nino more often though) I don’t see what would lead one to link climate change to this tornado season via the La Nina. It’s a natural phenomenon, so JNG’s statement is a little confusing to me.
Yeah, they were saying the most recent Australian drought was caused by global warming.
The reasoning being that warming oceans would necessarily result in fewer La Niñas.
Then a deep La Ni̱a arrived Рcaused heartbreaking but run-of-the-mill flooding Рand the Australian Green Party blamed coal miners.
The Catastrophic Global Warming Hypothesisis like one of those funny Dungeons & Dragons dice with “bullshit” embossed on every face.
Andrew_FL–
My impression is JNG does not link the current tornado season to climate change. He is saying that droughts in Texas, floods on the MIss and tornadoes are linked to each other. These are linked through a common cause– that is La Nina.
La Nina happened before climate change and after climate change. So, the droughts,floods and tornadoes are linked– but by something that has nothing to do with climate change.
This is different from what the video would insinuate which is that all must be linked through climate change.
Mind you, if I understand JNG correcting not ruling out the possibility that climate change could have some effect on the strength of droughts, tornadoes and floods. But we know there is a link between the droughts, tornadoes and floods: It’s La Nina. We experienced a fairly strong La Nina. That’s the apparent link.
Oh, that makes more sense. Provided each of those phenomena are connected to La Nina, they are, in some sense connected to each other. Anyone know of studies investigating links between droughts/floods and La Nina? I’ve seen some tornado studies but not drought/flood studies, and from what I’ve gathered the signals with those are less coherent in general.
JNG talks about a Marc Morano. Is this an early photo of him in the link?
http://www.shorpy.com/node/2353
I obviously notice this typo: His name is Nielsen 🙂
Propaganda is so much easier to do than science!
Andrew FL: On tornado signals vs ENSO? If there is a link its subtle.
http://www.esrl.noaa.gov/psd/csi/events/2011/tornadoes/enso.html
There is no apparent relation between ENSO and tornado outbreaks, except that it seems to follow serial monogamy. In the 9 outbreaks 1925-1965, none were la Nina. In the 9 outbreaks 1974-2011, 8 were la Nina or neutral.
If I had to guess, the outbreaks seem to occur when the general climate pattern is temporarily reversed.
Or, maybe there is a threshold effect. Below a certain temperature, outbreaks need a warming el Nino. Above a certain temperature, outbreaks need a cooling la Nina.
Or, its all just clusters with no real order.
Or, something else is the driver of outbreaks.
The interesting thing is how years of calm weather are, in the minds of the believers, forgotten as soon as an extreme weather event occurs.
Regarding the ENSO and the tornado outbreaks, one has to keep in mind the lag impact as well.
Most ENSO events peak in December, the lag of 3 months puts temperatures lowest in March. And then one of the greatest impacted regions is north-west North America down to Minnesota. This keeps the snow on the ground late into March and even mid-April while it is normally is gone in early March. A La Nina will also leave the south-east US warmer and drier than normal.
Cold north-west, warm south-east and greater than normal precipitation and storms result in between the two areas. (The opposite pattern occurs in an El Nino). This also explains why the outbreaks are almost exclusively in the April to May period and why they occur where they do, in the east-mid-west.
Now La Nina conditions are not always going to result in large tornado outbreaks. There are many factors which go into tornado outbreaks.
If I go through the NOAA tornado outbreak dataset linked above back to 1945, I find that 7 of the 13 outbreaks occur at the bottom of a La Nina cycle (when it is lagged 3 months). Only 1 occurs when an El Nino is transitioning. There is lots of El Ninos and La Ninas when there are no large outbreaks.
So, it is not the strongest of links but the numbers and the physical explanation are weighted more towards tornado outbreaks occuring during a La Nina than otherwise.
http://img232.imageshack.us/img232/8903/tornadolanina.png
I think the video conveys rather succinctly what might be in store for the voting constituencies, in at least this country, in motivating them to act now rather than later on AGW mitigation. You take current weather events and build them into something that shows immediate consequences and therefore warrants immediate actions. This approach is the favored course in getting things “done” in US politics today.
I think John N-G takes the luke-warmist path in the matter by indicating that any change in severity of some weather variables might be influenced a bit by AGW but not to the extent that was being implied in the video.
The difference in approaches above are similar to a number of warmists apparent view of their opposition as exclusively denialists and not considering the arguments of luke-warmists, who might say that, yes, GHGs have increased global temperatures (we understand the physics) but that does not directly provide evidence for all the disastrous outcomes envisioned by warmists and that all consequences need be detrimental.
John N-G does not consider himself a luke-warmer. I think he may takes the view that overselling is dangerous and possibly counter-productive. But I’m speculating– you could ask him.
Les Johnson (Comment #77012)- The data before recent decades is totally unreliable, given how monitoring has improved. If you look at data since 1950ish and the strongest tornadoes, there is some association. Looking at the data that early is going to get totally nonsense results.
That wasn’t a climate crock video made by “greenman.”
CCE–Thanks. Corrected.
“John N-G does not consider himself a luke-warmer.”
That does not mean he could not have taken a luke-warm approach. To be honest I could not care less what he considers himself.
This week I reread Michael Crichton’s novel “State of Fear”, which I hadn’t read since it was first published. I was struck by the similarity between the points raised in the video and the fictional “Sudden Climate Change Conference” that Crichton created, where every weather (and even tsunami) event was attributed to man made climate change. The video creators appear to reflect the same mind-set as Crichton’s villains. I hope they are not as sinister, but only misguided. Let’s hope they don’t find a way to create suitable disasters.
Would we not expect, a priori, that increasing the amount of thermal energy within a climate system would increase the strength of associated climate events?
Maybe as a rule of thumb– but that doesn’t mean tornadoes would be stronger because tornadoes are affected by shear and so their strength and frequency could decrease. So, “… Harold Brooks the world’s foremost tornado expert evidently thinks tornadoes are just as likely to weaken as strengthen as a result of climate change. “
Owen:
Just having (slightly more) thermal energy isn’t a sufficient condition for observably more violent weather. Doubling CO2 doesn’t double the thermal energy available, it maybe increases it by 1%.
If you want to look for effects, you need to look at what happens when the Hadley cells expand, or the regional climate effects from changing patterns of arctic ice freeze/thaw. (Places where the effects of warming get amplified through some regional-scale feedback.)
For US tornados, the dominant effect is the interaction of the southern jet stream with outflow from the Gulf of Mexico and the geography of the central plains.
(I’ve run across the claim that an increased irrigation in the central plains could leader to more severe outbreaks. Whether this is true or not, AGW driven climate change doesn’t always have to just be the bugaboo of anthropogenic CO2 emissions.)
The key drive of many severe weather systems, particularly the tropical ones is not thermal energy, but the energy stored in water vapour. This energy is proportional to the amount of water vapour, not to the temperature, and goes up quite steeply with a temperature increase.
In the lead up to the big floods in Brisbane there was much speculation in the weatherzone forums from experienced stormchasers that a big event was looming, and much of this speculation was driven by the unusually high level of water vapour available.
And if you consider tornadoes and hurricanes together, then increased water vapour availability due to higher temps should be a boost in severity for both events. However increased wind shear should boost tornadoes and reduce hurricanes, and vice versa. Perhaps it is possible that shear will increase in hurricane regions and decrease in tornado regions, but it does seem likely that the impact of wind shear on overall severe weather will be reduced due to the opposite effects on tornados and hurricanes cancelling out to some extent.
And the ENSO link is significant, as I think it is highly unlikely that warming the planet will not have some impact on ENSO. Changes in heat content are very important in the ENSO cycle. How ENSO may change is pretty unknown at this stage with different models contradicting each other. The theory that warming would result in more El Ninos was given some signficant legs in the 90s as the SOI reached unprecedented -ve (El Nino) average levels over about a 15 year period in the 80s and the first half of the 90s. But since then SOI has rebounded and now has been averaging positive (La Nina) since the end of the 98 El Nino.
The average SOI for Sep-Apr just gone was 21.9. The previous highest SOI over an equivelant period was 17.5. Thats quite a big jump, and certainly enough to explain unprecedented extremes for anything that is strongly linked to ENSO. It is also a big enough jump to speculate about a link with ENSO and global warming. But the unprecedented -ve SOI values of the 80s and 90s must be remembered. Perhaps AGW means more severe ENSO swings in both directions. Variability in SOI has certainly been much higher since about 1980, and was also higher from 1880 to around 1930 which was also another period of global warming.