bdgwx

I thought you all might be interested in this. I created the following plot using 4 traditional, 2 satellite, 1 raob, and 1 reanalysis datasets of the global mean temperature including an equal weighted 3 month centered composite of the 8 datasets and compare everything with the CMIP5 ensemble mean from 1979/01 to 2021/08. All timeseries are using the same baseline for comparative purposes. The composite trend is +0.19 C/decade.

The NSIDC site now has an http link for their data. This is useful since many browsers no longer support FTP. https://masie_web.apps.nsidc.org/pub/DATASETS/NOAA/G02135/seaice_analysis/

Per the official 12Z NHC wind profiles the IKE is 33 TJ. Per the RAMMB profiles the IKE is the 80 TJ. I'm a little suspicious of the NHC wind profiles but if we split the difference that would give us 56 TJ. This is a pretty big deal.

Using the wind radii from the 3Z NHC advisory with VMAX = 90 kts and RMW = 10 nm the IKE has increased to 32 TJ.

Per the official 21Z update the IKE is now 23 TJ.

** 2021 ATLANTIC RI INDEX AL092021 IDA 08/28/21 18 UTC ** (SHIPS-RII PREDICTOR TABLE for 30 KT OR MORE MAXIMUM WIND INCREASE IN NEXT 24-h) Predictor Value RI Predictor Range Scaled Value(0-1) % Contribution 12 HR PERSISTENCE (KT) : 20.0 -49.5 to 33.0 0.84 14.8 850-200 MB SHEAR (KT) : 10.7 30.1 to 2.3 0.70 5.7 HEAT CONTENT (KJ/CM2) : 88.0 0.0 to 151.8 0.58 4.3 STD DEV OF IR BR TEMP : 8.2 36.6 to 2.8 0.84 7.0 MAXIMUM WIND (KT) : 90.0 22.5 to 137.5 0.62 4.2 BL DRY-AIR FLUX (W/M2) : 212.2 895.4 to -55.0 0.72 4.8 2nd PC OF IR BR TEMP : 0.3 2.9 to -2.9 0.45 2.2 POT = MPI-VMAX (KT) : 67.3 28.3 to 146.3 0.33 1.0 D200 (10**7s-1) : 31.0 -29.7 to 185.9 0.28 0.8 %area of TPW <45 mm upshear : 0.0 100.0 to 0.0 1.00 0.6 SHIPS Prob RI for 20kt/ 12hr RI threshold= 52% is 10.7 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 56% is 5.2 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 46% is 6.7 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 39% is 10.0 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 30% is 12.5 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 21% is 4.5 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 12% is 2.6 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 0% is 0.0 times climatological mean ( 5.3%) Matrix of RI probabilities ------------------------------------------------------------------------------ RI (kt / h) | 20/12 | 25/24 | 30/24 | 35/24 | 40/24 | 45/36 | 55/48 |65/72 ------------------------------------------------------------------------------ SHIPS-RII: 52.3% 56.1% 45.6% 39.1% 29.9% 20.6% 12.2% 0.0% Logistic: 26.0% 42.2% 32.2% 17.4% 8.8% 12.1% 9.3% 1.2% Bayesian: 26.0% 55.7% 25.6% 53.5% 15.3% 5.7% 0.1% 0.0% Consensus: 34.8% 51.4% 34.4% 36.7% 18.0% 12.8% 7.2% 0.4% DTOPS: 46.0% 21.0% 19.0% 15.0% 2.0% 0.0% 0.0% 0.0%

Ultimately it boils down to the fact that station moves, instrument changes, time-of-observation changes, etc. all contaminate the record with known biases. These biases must be addressed. It is that simple. It is unethical at best to use the unadjusted data when reporting climatic information like the warming rate, heat waves, etc. given these documented biases especially if you have been notified of the existence of the issue.

Here is a great post by Gavin Schmidt on the ECS. https://www.realclimate.org/index.php/archives/2021/08/notallmodels/

It appears that the IPCC has adopted the phrase "practically ice-free" to mean the same thing as what we commonly use of "ice-free" to mean < 1e6 km^2 of extent. B.2.5 Additional warming is projected to further amplify permafrost thawing, and loss of seasonal snow cover, of land ice and of Arctic sea ice (high confidence). The Arctic is likely to be practically sea ice free in September at least once before 2050 under the five illustrative scenarios considered in this report, with more frequent occurrences for higher warming levels. There is low confidence in the projected decrease of Antarctic sea ice. AR6 WG1 SPM pg. 20. That is the prediction...2050 with a 66% likelihood.

Correct. Note that "likely" means 66% likelihood and "very likely" means 90% likelihood. The "very likely" range is 2.0-5.0C. The "likely" range is 2.5-4.0C. This is the first report that provides a best guess...3C. The IPPC divides the assessment reports into 3 parts called working groups. WG1 is the Physical Science Basis, WG2 is Impacts, Adaptation, and Vulnerability, and WG3 is Mitigation of Climate Change. It may be the WG2 report that is expected to be released in March '22.

This will take months to read, but the headline topic of equilibrium climate sensitivity comes as a surprise to me. I was not expecting the big jump from 1.5 to 2.5C on the lower bound. A.4.4 The equilibrium climate sensitivity is an important quantity used to estimate how the climate responds to radiative forcing. Based on multiple lines of evidence, the very likely range of equilibrium climate sensitivity is between 2°C (high confidence) and 5°C (medium confidence). The AR6 assessed best estimate is 3°C with a likely range of 2.5°C to 4°C (high confidence), compared to 1.5°C to 4.5°C in AR5, which did not provide a best estimate. SPM pg. 14

If 8/6 ends up being the minimum that would be epic indeed.

The long awaited Assessment Report 6 from the IPCC Working Group 1 regarding the Physical Science Basis Report has been released. https://www.ipcc.ch/report/ar6/wg1/

Some sea ice coupled GCMs did show that the 2020's could be a stall decade, but definitely not a recovery. I don't even know how a recovery could be possible considering the planetary energy imbalance is sitting at close to +0.9 W/m2 right now. And it might even be increasing at that. And given that environmental conditions this year should have promoted higher sea ice extent/area and yet we're still well below average is rather telling. Recovery is a pipe dream.

RSS matches RATPAC better. https://www.ncdc.noaa.gov/sotc/upper-air/201813 The claim that UAH matches radiosondes better comes from Dr. Spencer and Dr. Christy themselves. They also use IGRA as their radiosonde data source. The IGRA website warms users against using their dataset for long term trend analysis. How can you know that UAH (or any dataset for that matter) is "true" and thus a gold standard?