Climate Change Banter

[PhillipS]

Bethesda Boy is intellectually incapable of manning up and admitting when he's wrong - he'll just play semantic games and torture the English language forever.  I have no idea whether his issues stem from his admitted substance abuse, or underlying congenital flaws - but I hope that at some level he understands that he is his own worst enemy, and that he is solely responsible for his credibility these days being too low to measure. 

[LithiaWx]

Maybe you interpreted it that way, but that's definitely not was I was trying to say. See my post below, I was referring to the idea that macroscale homogenization was taking place.

If you won't let this go, this roundabout will continue forever.

The last sentence is why you're the problem here.

[ORH_wxman]

The last sentence is why you're the problem here.

Agreed. I don't think anyone believes his argument. Just admit you were initially (or the 2nd revision) was wrong and move on.

[StudentOfClimatology]

Fine. I had a bizarre change of mind that lasted 15 minutes. The sentence in reference was wrong. I was wrong. Is that an adequate admission?

Getting back on topic, my initial argument still stands. The shorter term divergence between the satellite and radiosonde data can be largely attributed to inhomogeneities in the radiosonde data. The majority of the peer reviewed literature comparing the two reaches the same conclusion.

[skierinvermont]

Fine. I had a bizarre change of mind that lasted 15 minutes. The sentence in reference was wrong. I was wrong. Is that an adequate admission?

Getting back on topic, my initial argument still stands. The shorter term divergence between the satellite and radiosonde data can be largely attributed to inhomogeneities in the radiosonde data. The majority of the peer reviewed literature comparing the two reaches the same conclusion.

 

This is progress.

 

I'd also like an apology for all the names you called me when I pointed this out and an apology for de-railing the thread for a week because you couldn't admit this until now.

[StudentOfClimatology]

This is progress.

I'd also like an apology for all the names you called me when I pointed this out and an apology for de-railing the thread for a week because you couldn't admit this until now.

I'm sorry if I called you any names. Personal attacks are unproductive and uncalled for.

That said, I'm sticking with the consensus of the peer reviewed literature regarding the error potential in the radiosonde data. In the shorter term (<15yrs), most of the divergence between the two can be attributed to inhomogeneities in the radiosonde data.

Obviously this is all debatable still, and I'm sure you disagree, so I hope we can end this on a positive note.

[LithiaWx]

Fine. I had a bizarre change of mind that lasted 15 minutes. The sentence in reference was wrong. I was wrong. Is that an adequate admission?

Getting back on topic, my initial argument still stands. The shorter term divergence between the satellite and radiosonde data can be largely attributed to inhomogeneities in the radiosonde data. The majority of the peer reviewed literature comparing the two reaches the same conclusion.

Didn't think you would, glad you did. Agree to disagree and move on is usually the best bet.

[skierinvermont]

I didn't create any disruption. My words were clearly out of context.

The peer reviewed literature supports my point of view. This is Fu/Randel et al 2005, back when the radiosonde data was running colder than the satellite data, for the same reason(s) it's now running warmer.

http://acd.ucar.edu/~randel/JCli_2006.pdf

 

 

OK now that that is over, we can move on to the peer-reviewed studies you posted. Again, I find this above post to be misleading as well.

 

Fu/Randel found there were some cool biases remaining in LKS 1979-2004.

 

First of all, RATPAC may have corrected for some of these biases since RATPAC is a bit warmer than LKS.

 

Second, the fact that there were cool biases 1979-2004 does NOT imply there are warm biases 2004-2015. You have provided no evidence of such. Your conclusion drawn from Fu/Randel is pure assumption and quite misleading.

 

 

There is considered to be moderate uncertainty associated with radiosonde data which could be in either the warm or cool direction. This does not limit the utility of radiosonde data vs MSU data, because MSU data is also considered to have comparable if not higher uncertainty.

[StudentOfClimatology]

OK now that that is over, we can move on to the peer-reviewed studies you posted. Again, I find this above post to be misleading as well.

Fu/Randel found there were some cool biases remaining in LKS 1979-2004. First of all, RATPAC may have corrected for some of these biases since RATPAC is a bit warmer than LKS.

The majority of the divergence between the satellite data and the radiosondes can actually be attributed to the lack of spatial coverage in the radiosonde data

http://www.remss.com/measurements/upper-air-temperature/validation.

That said, you're referring to RATPAC-A, which matches the satellite data more closely than RATPAC-B (though the IGRA data is probably preferable). The RATPAC-B dataset runs warmer after 1997 due to the transition off LKS and onto IGRA station data from 1997-2005, as the two are relatively inhomogeneous. There have (so far) been no adjustments to account for the noted bias in the LKS data.

When RATPAC switched their primary radiosonde dataset, they needed to homogenize it for continuity. The problem is the cool bias in the earlier data was left uncorrected for, so the smoothed final product depicts a somewhat unrepresentative trendline in the timeframe of interest.

Second, the fact that there were cool biases 1979-2004 does NOT imply there are warm biases 2004-2015. You have provided no evidence of such. Your conclusion drawn from Fu/Randel is pure assumption and quite misleading.

It's not that there are warm biases now, it's that they have yet to correct for the cool biases in the data through 2005. Do you not think that cooler biases in the data through 2005 will affect the trendline?

There is considered to be moderate uncertainty associated with radiosonde data which could be in either the warm or cool direction. This does not limit the utility of radiosonde data vs MSU data, because MSU data is also considered to have comparable if not higher uncertainty.

The RSS team investigated the reasons for the differences between the satellite data and the radiosondes, and determined that over 80% of the divergence is due to the lack of spatial coverage in the radiosonde data. By sub-sampling the RSS data only in the regions where the radiosonde data measures, the trendline swerve brought back into relative agreement.

http://www.remss.com/measurements/upper-air-temperature/validation

In the long term, the radiosonde datasets and satellites have equal uncertainty estimates, according to AR5.

[Mallow]

It's not that there are warm biases now, it's that they have yet to correct for the cool biases in the data through 2005. Do you not think that cooler biases in the data through 2005 will affect the trendline?

 

It depends. If the cool bias isn't changing with time, it by definition won't affect the trendline.

[StudentOfClimatology]

It depends. If the cool bias isn't changing with time, it by definition won't affect the trendline.

They didn't just abruptly switch from LKS to IGRA after 1997. They had to correct for the inhomogeneity between the two datasets during the transition, and the IGRA dataset was/is warmer than LKS. The last adjustment to the LKS data was in 2004, which did not sufficiently correct for the cold bias noted in the literature, which finds a cold bias in the RATPAC data through 2006.

The IGRA data doesn't have this problem, and it matches the satellite data more closely than either RATPAC-A or RATPAC-B.

[StudentOfClimatology]

The majority of the divergence between the satellite data and the radiosonde data can be attributed to the lack of spatial coverage in the radiosonde data. The RSS team did a thorough analysis of the this issue:

To account for the lack of spatial coverage in the radiosonde data, the RSS team sub-sampled the RSS data only in the regions where the radiosonde data measures. This corrected most of the divergence between RSS and the radiosonde data, suggesting that the lack of spatial coverage in the radiosonde is responsible for the majority of the divergence between the two.

http://www.remss.com/measurements/upper-air-temperature/validation

To illustrate the importance of sampling, we performed two comparisons using TLT data. In the first, we calculated area weighted global averages for each dataset, ignoring whether a given pixel in the satellite data was sampled by the radiosonde dataset - we will call these raw global averages. In the second, we calculated area-weighted dataset only using those pixels that were sampled by both the satellite and the radiosonde dataset. Note that this results in multiple versions of the subsampled satellite data, one for each radiosonde dataset.

Here we plot 5 time series for globally averaged HadAT data, the "raw" RSS and UAH time series, and the HadAT-subsampled RSS and UAH time series. In this case, differences between HadAT and both satellite datasets are reduced significantly by subsampling. This occurs for both the long-term trends and the short time scale differences.

[mob1]

Bacon Strips needs to get laid ASAP, I get that tempers flare in the arctic sea ice thread, but for someone who contributes pretty much nothing to attack someone who adds so much is just sad (regardless of which "side" you stand) his lame attempts of bravado make me want to puke. I have nothing with ORH but I enjoy the discussion in that thread and there's plenty of bickering from alarmists and deniers alike that I sift through, but all of the baconators posts are some form of personal attack with zero insight. We get it, you don't like a certain poster, move on...

[AvantHiatus]

Safe to say the Arctic is on its last legs. Along with so many other features of the old climate system. Sh** is really going to hit the fan post-2020.

 

In the event you haven't realized it by now, we needed a 2014-type season in order to make it thru a post-el nino melt season with summer ice cover in the arctic. Additionally, this is not any ordinary el nino, it is a Godzilla-level heat beast superimposed on a steady AGW warming trend.

[AvantHiatus]

Posted to reflect on the recent expansion of tropical convection inside the mid-atlantic coastal waters.

http://www.nature.com/ngeo/journal/v3/n12/abs/ngeo1008.html

 

 

 

Deep convection over tropical oceans is observed generally above a threshold for sea surface temperatures^{1, 2, 3, 4}, which falls in the vicinity of 26–28 °C. High-resolution models suggest that the related sea surface temperature threshold for tropical cyclones rises in a warming climate^5, 6. Some observations for the past few decades, however, show that tropical tropospheric warming has been nearly uniform vertically^7, 8, suggesting that the troposphere may have become less stable and casting doubts on the possibility that the sea surface temperature threshold increases substantially with global warming. Here we turn to satellite observations of rainfall for the past 30 years. We detect significant covariability between tropical mean sea surface temperatures and the convective threshold on interannual and longer timescales. In addition, we find a parallel upward trend of approximately 0.1 °C/decade over the past 30 years in both the convective threshold and tropical mean sea surface temperatures. We conclude that, in contrast with some observational indications, the tropical troposphere has warmed in a way that is consistent with moist-adiabatic adjustment, in agreement with global climate model simulations.

[AvantHiatus]

[Santa Claus]

I guess this is a banter post, whatever.

 

I think we are screwed.  Really profoundly screwed.  I won't hazard a guess at the long term implications of major AGW (perhaps there might even be benefits somehow realized from it), but there's major basic logistical issues from coastal areas being drowned.  And it's hard to see how that's not going to be a central issue of climate change.

 

And that's not even bringing in ecological disruption.  Migration pattern disruption, proliferation of certain diseases, etc.  Even before we ever get into the finer details of what will happen we have to get over displacing hundreds of millions, billions of people.  That freaks me out.

[The_Global_Warmer]

We have seen major changes in the polar regions with small warming.

The arctic is expected to be 5-9C warmer by 2100. Most of that will be in April, May, and October.

I think if global weather patterns change it will be when the high lat oceans are much warmer. When arctic circle snow cover melts in April and is gone by May.

Who knows.

But I have no doubt methane will start rising much faster over the next decade

[stadiumwave]

http://www.usatoday.com/story/weather/2014/12/08/california-drought-cause-noaa/20095869/

[AvantHiatus]

We got crushed by the research about 2C above baseline being a danger limit since it massively shrinks the timewindow for mitigation efforts and the adaptation road is a dead end at least for civilization as it currently exists. No joke, this is something recent. I've only realized what path we were on since 2013.

 

I'd say winter 2011-2012 and Hurricane Sandy was the catalyst and the overall connecting blockiness with AGW and Arctic melt, which to the best of my knowledge this connection cannot be dis-proven. Which is why calling Sandy a 1-500 year event never made any sense and damaged our understanding of the big picture where it matters.

 

That particular setup may not ever occur again but there is more or less a new suite or class of storms that exist in our scenario bank that are not accounted for by past analogs and of which will occur over the next few decades for certain.

 

Deep down, I wish I knew what I know now 15 years ago and was capable of making policy decisions back then. On the flipside, ignorance is bliss.

[AvantHiatus]

http://www.usatoday.com/story/weather/2014/12/08/california-drought-cause-noaa/20095869/

Global Warming does not mean wetter everywhere. What a flawed study. North America was a arid savanna during the pliocene, pretty much wall-to-wall.

[ORH_wxman]

Global Warming does not mean wetter everywhere. What a flawed study. North America was a arid savanna during the pliocene, pretty much wall-to-wall.

 

North America was drier 100 years ago than today...and during much of the LIA, California had horrific drought.

[AvantHiatus]

North America was drier 100 years ago than today...and during much of the LIA, California had horrific drought.

A nasty brew of natural and AGW influence could certainly be at work. Afterall, it is how arctic ice collapsed so quickly.

[PhillipS]

http://www.usatoday.com/story/weather/2014/12/08/california-drought-cause-noaa/20095869/

 

That article is from Dec 2014, and has been superseded by more recent research.  Since you like USAToday here is their more recent article on this topic [link[   But there is peer-reviewed research out there, too.  The Diffenbaugh et al 2014 paper from PNAS is a good start [link].  It's abstract:

 

California ranks first in the United States in population, economic activity, and agricultural value. The state is currently experiencing a record-setting drought, which has led to acute water shortages, groundwater overdraft, critically low streamflow, and enhanced wildfire risk. Our analyses show that California has historically been more likely to experience drought if precipitation deficits co-occur with warm conditions and that such confluences have increased in recent decades, leading to increases in the fraction of low-precipitation years that yield drought. In addition, we find that human emissions have increased the probability that low-precipitation years are also warm, suggesting that anthropogenic warming is increasing the probability of the co-occurring warm–dry conditions that have created the current California drought.

[The_Global_Warmer]

The heat is a major factor.

This heat is unprecedented in our records.

[stadiumwave]

The heat is a major factor.

This heat is unprecedented in our records.

It's well known that drought intensifies the heat....not vice versa

[chubbs]

April 2015 snowpack in the Sierra Nevada was 5% of normal - unprecedented in snowpack record and 500 year tree-ring proxy.

 

http://www.nature.com/articles/nclimate2809.epdf?referrer_access_token=8U88K0Q

[StudentOfClimatology]

April 2015 snowpack in the Sierra Nevada was 5% of normal - unprecedented in snowpack record and 500 year tree-ring proxy.

http://www.nature.com/articles/nclimate2809.epdf?referrer_access_token=8U88K0Q

No tree ring proxy will capture snowpack variability on a year-to-year resolution. I'm fairly certain this paper doesn't claim otherwise.

[csnavywx]

It's well known that drought intensifies the heat....not vice versa

Higher temperatures increase evaporation and evapotranspiration, so it most definitely does matter what the temperature does. The effects are mutualistic.

[skierinvermont]

No tree ring proxy will capture snowpack variability on a year-to-year resolution. I'm fairly certain this paper doesn't claim otherwise.

 

False. As they point out in the first few paragraphs, the tree ring record reliably captured the extreme droughts of 1934 and 1977 demonstrating year-to-year resolution. This year is worse. Yet again you are jumping to conclusions based on what you want to believe without actually reading. It took me 20 seconds to find this information and another minute to write this post.

 

Our reconstruction shows strong statistical skill but underestimates anomalously high snow water equivalent over the instrumental period (for example in 1952 and 1969). However, snow water equivalent lows (for example in 1934 and 1977) are reliably captured and our reconstruction reveals that the 2015 low is unprecedented in the context of the past 500 years.