Climate Change Banter

[AvantHiatus]

Also, how the heck do you go from warmest Jan-Mar to coldest Jan-Mar on record within 3 years (New York)? That is seriously messed up, yet our historical record is so small. I'd wager this temperature oscillation has not occured for 500-1000 years or more.

[StudentOfClimatology]

Also, how the heck do you go from warmest Jan-Mar to coldest Jan-Mar on record within 3 years (New York)? That is seriously messed up, yet our historical record is so small. I'd wager this temperature oscillation has not occured for 500-1000 years or more.

*bangs head on desk*

[nflwxman]

You seem to like the idea of squashing debate...not sure why.

 

 

New york's graph

 

 

Solid evidence this is occurring, but one graph from one state really doesn't prove it.

[ORH_wxman]

Solid evidence this is occurring, but one graph from one state really doesn't prove it.

 

 

Very debatable evidence I would say...there's papers that strongly criticized the Francis "wavy jet" theory. So I wouldn't overstate the influence.

[nflwxman]

Very debatable evidence I would say...there's papers that strongly criticized the Francis "wavy jet" theory. So I wouldn't overstate the influence.

There are, but the theory is technically and physically sound.  Whether or not it's occurring in greater frequency at 500mb will probably need a much larger sample size than the 20-30 years we have of trusted reanalysis data.

[ORH_wxman]

There are, but the theory is technically and physically sound.  Whether or not it's occurring in greater frequency at 500mb will probably need a much larger sample size than the 20-30 years we have of trusted reanalysis data.

 

 

This is a good paper to read for those who might be tempted to jump to conclusions on blocking based on short time periods....and also discusses methodology in blocking identification. (they use 3 different ways)

 

http://barnes.atmos.colostate.edu/FILES/MANUSCRIPTS/Barnes_DunnSigouin_etal_2014_GRL_wsupp.pdf

[AvantHiatus]

I honestly don't think it has anything to do with sea ice cover. It's more or less arctic warming in general and that is variable on a year to year basis via the latitudinal Delta T. This is too massive to be a coincidence or to occur by random chance. The temps are also in lockstep two-years in a row, 2014 Jan-Mar was a more extreme version of 2013 Jan-Mar.

 

You might say arctic sea ice has recovered yet blocking has remained, the recovery in extent was not significant enough to lower Arctic temperatures, and they continue to reside within their post-2007 levels.

[AvantHiatus]

Also, in the winter, we are still dealing with the same SIE we had before, and arctic temps tend to diverge farther away from average during the winter months.

[StudentOfClimatology]

I honestly don't think it has anything to do with sea ice cover. It's more or less arctic warming in general and that is variable on a year to year basis via the latitudinal Delta T.

Not catching this.

Thermal wind laws are just one factor of many that govern meridional mass transport potential.

This is too massive to be a coincidence or to occur by random chance. The temps are also in lockstep two-years in a row, 2014 Jan-Mar was a more extreme version of 2013 Jan-Mar.

Based on?

[AvantHiatus]

Let's go back to basics, west coast ridge = east coast trough (shallow, moderate, or deep). Do you deny this? The poleward extent of the ridge is most likely correlated in some way to the downstream extent of low pressure.

 

In rare cases, you can get a zonal flow over Eastern North America with a west coast ridge, especially during the summer due to the presence of the Bermuda high.

 

Made an error in my post, should of been Jan-Mar 2014/2015 for the correlation.

[AvantHiatus]

2014 

 

2015

 

[StudentOfClimatology]

None of that addresses the topic you were referring to.

[AvantHiatus]

None of that answers my question.

Touche, you've done it to several posters here before. I'll let the AMS community decide if this warrants any attention, take what you want from it. It seems to be a temporary phenomenon of natural variability meeting up with AGW in a climate that has only warmed by 0.9C.

 

http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2015/03/31/studies-conclude-climate-change-will-cause-less-severe-winters/

 

 

The BAMS study makes the unusual move (for an academic paper) of citing and then refuting the remarks of a political figure, White House science advisor John Holdren. Holdren, following the vicious January 7, 2014 “polar vortex” blast in the eastern U.S., stated in a video: “…the kind of extreme cold being experienced by much of the United States as we speak is a pattern that we can expect to see with increasing frequency as global warming continues.”

But a cold wave as powerful as the January 7, 2014 event will cease to exist by the end of the century, the BAMS study concludes.

“Continued Arctic sea ice loss is a major drive of decreased – not increased – North America cold extremes,” the study says. “Projected Arctic sea ice loss alone reduces the odds of such an event to one third by the mid twenty-first century, and to zero (or near-zero) by the late twenty-first century.”

The authors of both the Journal of Climate and BAMS studies express skepticism that Arctic amplification will meaningfully reconfigure the jet stream.

[Polar Vortex 2014]

Touche, you've done it to several posters here before. I'll let the AMS community decide if this warrants any attention, take what you want from it. It seems to be a temporary phenomenon of natural variability meeting up with AGW in a climate that has only warmed by 0.9C.

 

http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2015/03/31/studies-conclude-climate-change-will-cause-less-severe-winters/

 

I don't know. Looking at the New York state graph you posted, it looks like there's been 1.5-2C of warming over the period of record. If this was strictly natural variation, you would assume the same exact weather patterns could occur but that it would have been 1.5-2C colder (just due to the overall warming trend). Imagine what the graph would look like if you took off another 1.5-2C. It would be a massive outlier way outside the bounds of anything else that's occurred. Even 2014 would be a huge outlier with that correction. Maybe possible but it would probably be like a 1 in 1000 year event.

[ORH_wxman]

I don't know. Looking at the New York state graph you posted, it looks like there's been 1.5-2C of warming over the period of record. If this was strictly natural variation, you would assume the same exact weather patterns could occur but that it would have been 1.5-2C colder (just due to the overall warming trend). Imagine what the graph would look like if you took off another 1.5-2C. It would be a massive outlier way outside the bounds of anything else that's occurred. Even 2014 would be a huge outlier with that correction. Maybe possible but it would probably be like a 1 in 1000 year event.

 

Linear regression shows 1.3C of warming on the NY State graph...so if we took 2015's -6.8F and made it -9.2 based on 2.4F (1.3C) of warming, then we can calculate the sigma.

 

One standard deviation is 3.02F for a 3 month period ending in March for NY State. So -9.2 would be roughly 3 standard deviations below average. You would actually expect this to occur about 1 in 300 years.

[AvantHiatus]

AGW raises the probability to more like 1 in 50 years, thru various means such as increased blockiness. Very Sandy'ish in the way it reflects itself.

[ORH_wxman]

AGW raises the probability to more like 1 in 50 years, thru various means such as increased blockiness. Very Sandy'ish in the way it reflects itself.

 

 

You may want to read this paper before jumping to conclusions about blockiness:

 

http://barnes.atmos.colostate.edu/FILES/MANUSCRIPTS/Barnes_DunnSigouin_etal_2014_GRL_wsupp.pdf

 

 

I posted it upthread.

 

 

That idea is quite debatable as is self-explanatory given the papers out there.

[AvantHiatus]

You may want to read this paper before jumping to conclusions about blockiness:

 

http://barnes.atmos.colostate.edu/FILES/MANUSCRIPTS/Barnes_DunnSigouin_etal_2014_GRL_wsupp.pdf

 

 

I posted it upthread.

 

 

That idea is quite debatable as is self-explanatory given the papers out there.

It looks like the summer signal interferes with the trend. There is a clear increase during the winter and fall. We are in agreement tho that it has nothing to do with sea ice loss, not sure how this concept ever came about it.

 

In hindsight it looks ridiculous as all the sea ice does is act as a albedo source and slow down radiative transfer. It might eventually become a bigger factor but the largest factor in the most recent blocking era was the -NAO and Arctic Amplification.

[ORH_wxman]

It looks like the summer signal interferes with the trend. There is a clear increase during the winter and fall. We are in agreement tho that it has nothing to do with sea ice loss, not sure how this concept ever came about it.

 

In hindsight it looks ridiculous as all the sea ice does is act as a albedo source and slow down radiative transfer. It might eventually become a bigger factor but the largest factor in the most recent blocking era was the -NAO and Arctic Amplification.

 

 

No there isn't. Read the paper.

 

Only one of the 3 methods showed a significant winter increase...and the increases are time-sensitive too on starting and endpoints.

[AvantHiatus]

No there isn't. Read the paper.

 

Only one of the 3 methods showed a significant winter increase...and the increases are time-sensitive too on starting and endpoints.

How do we account for stuff like Snowmageddon, Sandy, and California heat/drought without bringing into play blocking? The paper can say all it wants but good science is not explaining a trend while only accounting for one variability.

 

Can we at least agree that North America has been a hotspot for increased blockiness? According to the paper, I would surmise that elsewhere has been 'normal'. It says Asia has enhanced blockiness during the winter.

[ORH_wxman]

How do we account for stuff like Snowmageddon, Sandy, and California heat/drought without bringing into play blocking? The paper can say all it wants but good science is not explaining a trend while only accounting for one variability.

 

Can we at least agree that North America has been a hotspot for increased blockiness?

 

How do we account for the blizzard of 1888, the March heat wave of 1910, the hurricane of 1938, the unbelievable cold (and western warmth) in February 1934, the epic California drought in 1977, and the blizzard of 1978 without bringing into play blocking?

[GaWx]

How do we account for the blizzard of 1888, the March heat wave of 1910, the hurricane of 1938, the unbelievable cold (and western warmth) in February 1934, the epic California drought in 1977, and the blizzard of 1978 without bringing into play blocking?

 

 To take this further, how do we account for the great (SE+) cold of Feb.'s 1835 (0 F in SAV!), 1895, and 1899? The great deep SE snowstorm of 1/1800? The 1893 'canes? The great SE heatwave of Sep. 1925?

[FPizz]

 To take this further, how do we account for the great (SE+) cold of Feb.'s 1835 (0 F in SAV!), 1895, and 1899? The great deep SE snowstorm of 1/1800? The 1893 'canes? The great SE heatwave of Sep. 1925?

Easy, not everything is GW.  It is weather.

[GaWx]

Easy, not everything is GW.  It is weather.

 

 I agree. However, AGW alarmists often blame just about every wx extreme on AGW with no evidence to back them up and as if extremes haven't always occurred. It has gotten out of control in some cases and even downright laughable.

 

 Katrina is one such example. What about how relatively quiet it has been with regard to US H hits in recent years? Also due to AGW? Us Tornado #'s have been down in recent years overall. Also due to AGW? They can't have it all of these different ways. Anyone with an ounce of common sense should realize this. Sorry.

[AvantHiatus]

I already stated it's a combination of natural variability and AGW. Feel free to keep making stuff up, this is basic stuff guys and is right in front of your face. 09-10 was my snowiest winter on record, you just cant make this stuff up.

[ORH_wxman]

I agree. However, AGW alarmists often blame just about every wx extreme on AGW with no evidence to back them up and as if extremes haven't always occurred. It has gotten out of control in some cases and even downright laughable.

Katrina is one such example. What about how relatively quiet it has been with regard to US H hits in recent years? Also due to AGW? They can't have it all of these different ways. Sorry.

The hurricane stuff quieted down somewhat after Chris Landsea's paper in 2010-2011. I'm sure the major hurricane landfall drought since 2005 has also helped. But I'd bet the hyperbole will start up again when we finally get a major hurricane landfall.

Attribution studies are very uncertain by nature. The problem is you need to understand the inherent extremes of meteorology first before making a connection to AGW on whether it increases or decreases the probability. About the only robust one globally is shifting the probability of heat waves and decreasing probability of cold waves...which of course makes sense in an overall warmer world.

[LithiaWx]

It's common sense guys, come on.

[GaWx]

How about the theory that the extremes have been increasing recently like we saw from

the 1910's into the 1930's due to warmer Arctic temperatures relative to the rest of the

Northern Hemisphere? You can also see the extremes decreasing as the Arctic 

cooled again after the 1930's into the 1970's. I guess you could say correlation

doesn't equal causation, but I would like to see a study that focuses on the last

100 years or so rather the last 30 to get some clarity on this issue.

 

bluewave,

 I bet the extremes of wx events of the 1880's to especially the 1890's were as extreme, if not more extreme in the US. Are you familiar with that period? Examples just for the 1890's just for the SE: The 1893 hurricane season was horrendous. That followed the biggest ATL snowstorm (still) on record in Jan. Feb. of 1895 had a huge N.O. snow and was the only month on record to give ATL two major snows. The winter of 1894-5 gave FL not one but two major freeze periods very far down. During the short span of Aug. 1898 through Feb. 1899, GA was hit by an unheard of two hurricanes just over a month apart (one was the strongest on record to hit GA) followed by a blizzard to the SE coast and well into FL in Feb., followed by the coldest on record in places like ATL (-9 F). That period reminds me of Sep-Dec., 1989 in CHS (Hugo/big coastal snowstorm Dec.).

 

Aside: I still wonder how much the solar cycles may have been one of the factors regarding extremes. Like with AGW, that would be extremely hard to prove. The sun was in a min. in the late 1800's to early 1900's.

The prior min. was in the late 1700's to early 1800's. During that period, SAV had what are still by far their biggest 2 snows on record and their coldest temp.

[ORH_wxman]

bluewave,

 I bet the extremes of wx events of the 1880's to especially the 1890's were as extreme, if not more extreme in the US. Are you familiar with that period? Examples just for the 1890's just for the SE: The 1893 hurricane season was horrendous. That followed the biggest ATL snowstorm (still) on record in Jan. Feb. of 1895 had a huge N.O. snow and was the only month on record to give ATL two major snows. The winter of 1894-5 gave FL not one but two major freeze periods very far down. During the short span of Aug. 1898 through Feb. 1899, GA was hit by an unheard of two hurricanes just over a month apart (one was the strongest on record to hit GA) followed by a blizzard to the SE coast and well into FL in Feb., followed by the coldest on record in places like ATL (-9 F).

 

Aside: I still wonder how much the solar cycles may have been one of the factors regarding extremes.

 

 

Two of the most extreme winters occurred during that time....1877-1878 was one of the warmest winters on record....many of the upper plains stations that have data back to that time still have it is their warmest winter on record, and it's not even close.

 

Then 1884-1885 was one of the coldest winters on record. You could also to a lesser extent throw in 1881-1882 for an extreme warm winter...not quite as widespread as the warmth in 1877-1878, but still exceptional. Another extreme cold winter in 1887-1888.

 

 

Unfortunately, our most comprehensive climate data mostly starts in 1895...which is really after that extreme period in the 1870s/1880s...and 2 years after the exceptional 1893 hurricane season.

[GaWx]

Two of the most extreme winters occurred during that time....1877-1878 was one of the warmest winters on record....many of the upper plains stations that have data back to that time still have it is their warmest winter on record, and it's not even close.

 

Then 1884-1885 was one of the coldest winters on record. You could also to a lesser extent throw in 1881-1882 for an extreme warm winter...not quite as widespread as the warmth in 1877-1878, but still exceptional. Another extreme cold winter in 1887-1888.

 

 

Unfortunately, our most comprehensive climate data mostly starts in 1895...which is really after that extreme period in the 1870s/1880s...and 2 years after the exceptional 1893 hurricane season.

 

 1877-8 being a very strong El Nino likely was a major factor for so much warmth in the N US. The two still warmest winters on record for ATL were way back in 1879-80 and 1889-90! I bet very few would have ever guessed that. These surrounded two very cold winters in 1884-5 and 1885-6 and were followed by the very cold periods already mentioned during the 1890's as well as the early 1900's.