bdgwx

https://apps.ecmwf.int/webapps/opencharts

Keep in mind that HadCRUT only covers 84% of the Earth. The nature of the coverage is such that the warming trend is biased low. Other datasets like those provided by NASA and Berkeley Earth address the coverage issue. And of course reanalysis datasets like that provided by ERA has homogeneous and complete coverage natively due to 3DVAR/4DVAR assimilation. Cowtan & Way 2013: Coverage bias in the HadCRUT4 temperature series and its impact on recent temperature trends http://www.ysbl.york.ac.uk/~cowtan/applets/trend/trend.html When you apply the "kriging" technique to HadCRUT to correct for the coverage bias the warming trend is +0.191C/decade which is spot on with other datasets like ERA (+0.1910C/decade), BEST (+0.1908C/decade), GISTEMP (+0.190C/decade). Trends are valid from 1979-present. In terms of using UAH and RSS as a proxy for the surface warming trend RSS (+0.214C/decade) is closer to the consensus than UAH (+0.137C/decade).

Those are fair points. Two additional ones we might add... 8) UAH TLT may be contaminated by the cooling stratosphere. 9) Concerns with their satellite merging process have raised.

Copernicus just released the September 2020 report based off the ERA reanalysis. https://climate.copernicus.eu/surface-air-temperature-september-2020 It is the warmest September on record. This brings the warming trend since 1979 up to +0.1910C/decade +- 0.005. In the last 24 months the trend has increased by 0.01C/decade. Using the baseline defined in the IPCC Global Warming of 1.5C report and taking the average of the last 12 months from ERA the warming since the industrial revolution is now 1.3C.

It is hard. No one said it was easy. That does not mean that scientists are incapable of measuring the global mean temperature and quantifying the uncertainty in that measurement. The uncertainty envelope is narrow enough that conclusions about Earth's rate of warming can be made with confidence. FWIW...I think RSS's 0.214C/decade rate of warming is likely higher than the true surface warming rate. Taking the mean of a sampling of several satellite, balloon, surface, and reanalysis datasets suggests that the true surface warming rate is probably closer to the 0.18C/decade from 1979 to present. This means UAH and RSS probably underestimate and overestimate the true warming rate respectively. Interestingly when you equally weight UAH and RSS you get a warming rate of +0.175C/decade which is pretty close to the mean warming rate suggested by other datasets. As I've said before I do not prefer either UAH or RSS over the other. Remember...in lieu of any compelling reason to discount a line of evidence the skeptical thing to do is equally weight those lines of evidence.

ADT is not handling this storm well. ADTv8 score is 4.8 at 15:30Z but ADTv9 score is only 3.9 at 15:50Z with an estimated pressure of 988mb. Just a bit off...

Here are the relevant publications. Karl 2015: Possible artifacts of data biases in the recent global surface warming hiatus Haung 2015: Extended Reconstructed Sea Surface Temperature Version 4 (ERSST.v4). Part I: Upgrades and Intercomparisons Haung 2015: Extended Reconstructed Sea Surface Temperature Version 4 (ERSST.v4): Part II. Parametric and Structural Uncertainty Estimations Rennie 2014: The international surface temperature initiative global land surface databank: monthly temperature data release description and methods Karl did not adjust temperatures upward. The upward revised estimate in the warming trend was a product of changes to the inputs and methodology used to analyze those inputs. What he did was switch from ERSSTv3 to ERSSTv4 and incorporated the International Surface Temperature Initiative into the analysis. In his own words here are the changes that he felt were most impactful. an increasing amount of ocean data from buoys, which are slightly different than data from ships an increasing amount of ship data from engine intake thermometers, which are slightly different than data from bucket seawater temperatures a large increase in land-station data, which enables better analysis of key regions that may be warming faster or slower than the global average First, SSTs are increasingly being acquired from buoys (like the ARGO network) which have been shown be more accurate than ship measurements. This provides the opportunity to use the buoy data as a means of calibrating or bias correcting the ship data especially when there is adequate colocation of the two. ERSSTv4 does that. Second, there was a dramatic shift in ship measurement technique after WWII in which the dominant method switched from bucket thermometers to engine intake thermometers. ERSSTv3 assumed that all measurements were bucket style after WWII, but it was discovered that several ships were, in fact, still performing the bucket measurements even up to 2015. ERSSTv4 fixed this discrepancy. Third, the incorporation of the ISTI into the analysis improved spatial coverage of land temperatures especially in the Arctic where the warming is significantly higher than the global average. As a side note...John Christy (the primary maintainer of the UAH satellite dataset) is listed as a contributor to the ISTI dataset (see Rennie 2014 above) which Karl felt represented the biggest impact to the upwardly revised warming trend. And it's important to note that despite these changes the net effect of all adjustments to the data still results in a lower warming trend than would be computed otherwise over the entire period of record. Again...the warming is not a result of Karl's changes. Karl's changes result in a better estimate of the warming that was already there and which occurred because of the positive Earth Energy Imbalance which itself is driven by the net effect of all climate forcing agents. And besides, Karl is but one among many maintainers of the dozen or more datasets that publish a global mean temperature. His dataset is not significantly different from the other datasets.

18Z COAMPS is tame with the potential Yukatan landfall , but then explodes Delta into major hurricane in the GOM. One of those members is a cat 5.

And on the 6Z parallel GFS it is the other way around. Gamma ends up swallowing up Delta. It does seem like odds are increasing that we see a binary interaction.

12Z ECMWF is more aggressive with development now. It does seem like it is missing or at least underestimating initial development this year. 92L may end up developing enough that it tugs on Gamma and pulls that system north eventually as well.

There is a wide envelop of possible tracks from model guidance. GEFS shows it loitering in the GOM away from land for awhile. EPS shows it creeping south and hugging the coast. UKMET shows it moving into the northern GOM eventually.

Yet another study with significant implications. Official: Li et al 2020: Increasing ocean stratification over the past half-century Open access: use this link News article: Mixing of the planet’s ocean waters is slowing down, speeding up global warming, study finds, Washington Post, September 29, 2020 Abstract: Seawater generally forms stratified layers with lighter waters near the surface and denser waters at greater depth. This stable configuration acts as a barrier to water mixing that impacts the efficiency of vertical exchanges of heat, carbon, oxygen and other constituents. Previous quantification of stratification change has been limited to simple differencing of surface and 200-m depth changes and has neglected the spatial complexity of ocean density change. Here, we quantify changes in ocean stratification down to depths of 2,000 m using the squared buoyancy frequency N2 and newly available ocean temperature/salinity observations. We find that stratification globally has increased by a substantial 5.3% [5.0%, 5.8%] in recent decades (1960–2018) (the confidence interval is 5–95%); a rate of 0.90% per decade. Most of the increase (~71%) occurred in the upper 200 m of the ocean and resulted largely (>90%) from temperature changes, although salinity changes play an important role locally. This finding has a few implications. Reduced heat transport into the ocean depths means more heat is available to drive atmospheric temperatures upward. The faster warming of the ocean surface will reduce carbon uptake since uptake is inversely proportion to the ocean temperature thus resulting in less carbon buffering and an increase in the rate at which CO2 is accumulating in the atmosphere. The rate at which additional energy is becoming available to tropical cyclones is increasing. The increased stratification may disrupt the Atlantic Meridional Overturning Circulation causing it to slow down.

That is absolutely how the atmosphere works. Just considering ocean circulations alone is enough to explain persistent anomalies in atmospheric temperature. For example, if the AMOC slows down some regions will likely cool while others warm as the poleward heat movement is impeded. Sure, tropical cyclone activity (among other mechanisms) may increase and work to pull this heat poleward via atmospheric circulation as opposed to ocean circulation, but the distribution of that heat would almost certainly not be exactly the same as before. The paleoclimate record is convincing...climatic shifts do not work in perfect harmony between regional and global scales. The global mean temperature can warm while specific regional mean temperatures cool and vice versa.

Indeed, we are "rebounding" from the LIA. But "rebounding" is a NOT a cause. It is an observation. That rebound happened for a reason that likely includes many contributing factors. CO2 is certainly among those factors and its significance became most acute after 1950. UHI effects are NOT ignored. Every conventional surface based database I'm aware of gives the UHI effect its well deserved consideration. Berkeley Earth has a great publication detailing how much the UHI bias impacts global mean temperatures (see Rohde 2013). "We observe the opposite of an urban heating effect over the period 1950 to 2010, with a slope of -0.10 ± 0.24°C/100yr (2σ error) in the Berkeley Earth global land temperature average.. The confidence interval is consistent with a zero urban heating effect, and at most a small urban heating effect (less than 0.14°C/100yr, with 95% confidence) on the scale of the observed warming (1.9 ± 0.1°C/100 yr since 1950 in the land average from Figure 5A)." As you can see their conclusion is that the UHI effect is more likely to have a negative bias than a positive bias on global mean temperature trends after 1950 when the warming became most acute. The observed trends in the global mean surface temperature datasets is NOT a result of the UHI effect. It is a result of the planet actually warming.

This actually comes from Myhre 1998. Well...the 5.35 sensitivity parameter anyway. Myhre used radiative transfer models (LBL, NBM, BBM) using data from the well known HITRAN database. The logarithmic behavior was first diagnosed by Arrhenius 1896 so he usually gets credit for this mind numbingly simple back-of-the-envelope model of the climate system's response to changes in CO2 concentration. This model is so well know that it is typically regarded as common knowledge and is referenced ubiquitously often without citations in the climate community. BTW...Arrhenius' final computation (which is said have been very laborious) from 1908 using his more complex 1896 model yields 4C of warming for 2xCO2 (see Worlds in the Making by Arrenhius 1908). It is interesting that this falls comfortably within the official IPCC range and despite his primitive (by today's standards) understanding of the climate system. Wouldn't that be a remarkable feat of brilliance if his 4C estimate turns out to be close to the observed value?

The data says the Earth's climate was that steady for almost 2000 years on a global scale. Global/hemisphere proxy data temperature reconstructions do not ignore the MWP or LIA. Remember, the MWP and LIA were names given to periods of climatic shifts primarily in the North Atlantic periphery area (see Lamb 1982) though most scientist do accept some global influence albeit by a smaller amount. These North Atlantic sites are included in Holocene temperature reconstructions regardless. CO2 did lead temperatures in the past. The PETM is probably the best analog. Nevermind that an agent does not have to lead a variable for it to be a significant contributing factor to the trajectory of that variable anyway. CO2 is leading now because it is being released in huge quantities independent of any climate modulation.

If CO2 is not a significant contributing factor then what is?

Actually...it's worse than that. Present for paleoclimatology is defined as 1950. The chart is missing the last 145 years of warming prior to 2000. If it had include the last 165 years of warming up to 2020 then you'd see that today's temperature is at least as high as the Minoan Warm Period and probably would exceed the boundaries of the y-axis. The x-axis is also not scaled linearly which makes the temperature changes in the past appear more rapid than they really are. For example, the abrupt change around 8000 years ago only had a warming rate of 0.1C/decade as compared to about 0.4C/decade observed today. The chart comes from Dr. Easterbrook who actually used it in congressional testimony (https://www.youtube.com/watch?v=ofXQdl1FDGk). I have no idea how a PhD geology professor could bungle something so badly. And his predictions are just as bad. He predicted 1998 to be the peak and his middle of the range estimate for the cooling by 2020 is 0.7C below 1998. In reality 2019 ended 0.3C above 1998. Dr. Easterbrook's prediction is off by an astonishing 1.0C in only 20 years!

Consider a forced induction combustion engine. Air induction can both lead and lag the power level. When the turbocharger is internally forced via the exhaust the induction lags the power increase. When the turbocharger is externally forced via electric boost technologies the induction leads the power increase. In both cases the turbocharger is a significant contributing factor to the final power level of the engine. Earth's carbon cycle behaves in this manner as well. I think those that understand forced induction combustion engines will find the lead/lag behavior of CO2 in the climate system intuitive. BTW...BorgWarner does produce dual modulated turbochargers with both internal forcing (exhaust) and external forcing (electric).

There have been a few comprehensive style studies that have been published recently which try to provide the best estimates of critical metrics related to climate change based on the large body of evidence available at the time of publication. I am but an amateur, but it is my belief that these publications are impactful and that they are of the type that may appear prominently in the forthcoming IPCC AR6 report. If anyone has noteworthy or impactful peer-reviewed publications then by all means please post them to this thread. If possible provide a link to an open access (non pay-walled) version of the manuscript. Temperature Reconstruction Kaufman 2020: Holocene global mean surface temperature, a multi-method reconstruction approach Kaufman 2020: A global database of Holocene paleotemperature records Summary: The rate of warming during the contemporary era is likely unprecedented during the Holocene. The global mean temperature is very likely to be much higher than at any point in the last 2000 years and possibly even exceeding the Holocene Climate Optimum 6000+ years ago. Climate Sensitivity Sherwood 2020: An Assessment of Earth's Climate Sensitivity Using Multiple Lines of Evidence Summary: For 2xCO2 they report 2.6 - 3.9C and 2.3 - 4.7C for 66% and 95% certainty respectively with a value of 3.1C being at the peak of the probability distribution curve. It is noted that the upper bound should be considered more cautiously. It is far easier to constrain the lower bound than the upper bound. Values <= 1.5C can now be confidently ruled out. Using the IPCC's standard 66% confidence window this study suggests a refinement of the "official" climate sensitivity to 2.6 - 3.9C as opposed to the current range of 1.5 - 4.5C. Earth Energy Imbalance Schuckmann 2020: Heat stored in the Earth system: where does the energy go? Summary: The EEI is +0.87 +- 0.12 W/m^2 and is increasing. 1% goes into the atmosphere. 4% goes into the cryosphere. 6% goes into the land. 89% goes into the oceans. To pull the EEI back to 0 would require a change in CO2 concentration from 410 ppm to 353 ppm. For those that don't know EEI is the amount of forcing still needing to be equilibriated via an increase in temperature. It should not be confused with effective radiative forcing (ERF) which is the cumulative forcing after fast feedbacks (like water vapor, etc.) have played out. EEI goes to zero after the climate system fully equilibrates to the ERF. This publication says the following of EEI.."This simple number, EEI, is the most fundamental metric that the scientific community and public must be aware of as the measure of how well the world is doing in the task of bringing climate change under control."

Carbon Brief has a couple of excellent articles as well. https://www.carbonbrief.org/qa-how-do-climate-models-work https://www.carbonbrief.org/cmip6-the-next-generation-of-climate-models-explained

Atlantic Meridional Overturning Circulation. If ocean heat transport moving north increases/decreases then it only make sense that the atmospheric temperature response increases/decreases in the North Atlantic region as well. I'm having a hard time envisioning a mechanism by which the accumulation/depletion of a significant portion of heat in a particular region would not produce effects like the MWP and LIA. If anything the MWP and LIA are a testament to the fact that regions are more responsive to climate shifts as compared to the global scale. And we already know that the Earth is quite amendable to global scale climate shifts...a la...the PETM, other ETMx events, the glacial cycles, etc. Given the right nudge the Earth seems quite willing to undergo dramatic climate shifts that are magnified on regional scales. And we are giving the planet quite the nudge today; unprecedented at least through the Holocene.

People wonder why Dr. Spencer's reputation and legitimacy is being questioned. Well here you go... http://www.drroyspencer.com/2020/09/climate-hustle-2-premieres-this-evening-at-8-p-m/

In 1997 he put the 2xCO2 sensitivity at 0.3-0.5C (see Lindzen 1997). There is some equivocation in the paper above, but it sounds like he is now entertaining a value on the lower end of the IPCC range at about 1.5C. The rate at which his estimates have increased is about +0.45C/decade...faster than the actual warming rate. I will say that at least Lindzen proposes a legitimate hypothesis for supporting lower climate sensitivities...the iris effect. The question is...does Earth really have a mechanism like this that makes it resistant to climate change? The paleoclimate record seems to suggest that the Earth is quite amendable to large changes given the proper nudge and with each passing decade in the contemporary warming era we are constraining the lower the bound of sensitivities to higher and higher values. Each passing decade of warming is making Lindzen's iris effect and change resistant hypothesis appear less and less likely. BTW...A recent comprehensive style study puts the range at 2.6-3.9C and 2.3-4.7C for 1-sigma and 2-sigma confidence respectively (see Sherwood 2020 and free). Also, I just want to say that I do not condone the tone and rhetoric used against you. I do not think you are a liar, troll, or Russian (not that nationality matters). And while I do not think the body evidence supports the position you advocate for I still think you've handled yourself respectfully nonetheless. I think if you and I sat down for a beer (or coffee) we'd probably get along just fine. I still think you're wrong about climate science though

Here is Dr. Alley's data: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/isotopes/gisp2_temp_accum_alley2000.txt Notice that the rate of warming today is unprecedented during the Holocene per Dr. Alley. The warming rate is so high today that it smashes the record from that noticeable blip from 8210-7820 that admittedly looks pretty robust at first glance. The problem is that the x-axis on this specific graph has non-linear scaling (who does that?) and it is missing the contemporary warming era. This graph ends in 1855...a full 165 years in the past. If you stich on the last 165 years of warming we are at least close to the peaks of the Minoan warm period and Holocene climate optimum in the best case and may have already popped the bounds of the y-axis in the worst case. BTW...here's a good lecture by Dr. Alley if you want to hear his take on the science.