Assessment of climate change risk to the insurance sector

by Judith Curry

The insurance sector is abuzz with a new report from AIR Worldwide on the insurance risk from the impact of climate change on hurricanes.  Insurance industry clients of my company, Climate Forecast Applications Network (CFAN), have requested a critique of this report.

AIR Worldwide, a respected catastrophe risk modeling and consulting company, has recently published a report Quantifying the Impact from Climate Change on Hurricane Risk.  AIR’s assessment has three components:

  • Hazard component (relates to the frequency and intensity of events)
  • Engineering component (relates to physical assets at risk)
  • Financial component (relates to monetary losses)

The AIR Report purports to “capture the full range of plausible events that could impact an area.”

My critique focuses solely on the hazard component. A summary of my analysis is provided below:

  1. The driver for AIR’s assessment is warming associated with the emissions/concentration scenario RCP8.5, which AIR refers to as a ‘business as usual scenario.’  In fact, RCP8.5 is increasingly being judged as implausible by energy economists, and is not recommended for use in policy planning.
  2. The hurricane risk from climate change focuses on the number and intensity of U.S. landfalls in a changing climate.  Their scenario of the number of major hurricanes striking the U.S. by 2050 is judged to be implausible for medium emissions scenarios such as RCP4.5.
  3. The sea level scenarios used in the AIR Report are higher than the recent IPCC consensus assessments and are arguably implausible for medium emissions scenarios.
  4. The AIR Report ignores the ‘elephant in the room’ that is of relevance to their target period to 2050: the Atlantic Multi-decadal Oscillation (AMO). A shift to the cool phase of the AMO would arguably portend fewer major hurricanes striking the U.S.

For reference on the topics of hurricanes, sea level and climate change, see these reports recently published by CFAN:

  • Special Report on Sea Level and Climate Change  [Download Report]
  • Special Report on Hurricanes and Climate Change [link]


When considering scenarios of future climate change, there is much scope for uncertainty. Plausible outcomes (especially on the high end) are weakly constrained and there is much disagreement among experts as to the likely range of outcomes (67% likelihood).

Outcomes of future climate change are associated with deep uncertainty [for further context, see my paper on Climate Uncertainty and Risk].  Under conditions of deep uncertainty, probabilities of outcomes are not very meaningful. At best, we can hope to plausibly  bound the range of outcomes.  The IPCC seeks to bound the likely range [67%] of outcomes.

While experts will inevitably disagree on what constitutes a plausible best or worst case scenario when the knowledge base is uncertain, I have developed a classification  based on the extent to which borderline impossible parameters or inputs are employed in developing the scenario [see my essay What’s the worst case?]. This classification is inspired by the Queen in Alice in Wonderland: “Why, sometimes I’ve believed as many as six impossible things before breakfast.” This classification articulates three categories of worst-case scenarios:

  • Conceivable worst case: formulated by incorporating all worst-case parameters/inputs  into a model; the outcome does not survive refutation efforts.
  • Possible worst case (borderline impossible). Includes multiple worst-case parameters/inputs in model-derived scenarios; the outcome survives refutation efforts (at least temporarily).
  • Plausible worst case:  Includes at most one borderline implausible assumption in model-derived scenarios.

This classification is used here in evaluating the plausibility of AIR’s scenarios out to 2050.

How much warming?

AIR’s assessment of the climate change impact on U.S. hurricane risk is driven solely by warming from manmade emissions. Specifically, the AIR Report focuses on emission/concentration scenario RCP8.5.

While the emissions/concentration scenario RCP8.5 is often referred to as a ‘business as usual’ scenario, it is in fact an extreme scenario that is implausibly high. RCP8.5 pathways are driven by: very high population growth, very high energy intensity of the economy, low technology development, and a high level of coal in the energy mix. Wang et al. (2017) and Ritchie and Dowlatabadi (2018) challenge the bullish expectations for coal in the RCP8.5 scenarios, which is counter to recent global energy outlooks and exceeds today’s known conventional reserves. Burgess et al. (2020) further highlight the implausibility of the RCP8.5 scenario owing to contradictions in the assumptions used in constructing the scenario. Pielke and Ritchie (2020) concluded that RCP8.5 is systematically misused in applications of climate model simulations, particularly for policy making purposes. Ritchie and Dowlatabadi (2018) recommend that RCP8.5 not be used as a benchmark for policy studies.

The 2019 World Energy Outlook Report from the International Energy Agency (IEA) challenges the near-term RCP scenario projections through 2040 [link]. The IEA examined three scenarios: a current policy scenario where no new climate or energy policies are enacted by countries; a stated policies scenario where Paris Agreement commitments are met; and a sustainable development scenario where rapid mitigation limits late 21st century warming to well below 2°C. The IEA projections through 2040 are close to the RCP4.5 scenario (a moderate emissions scenario) and much lower than for RCP8.5.)

On timescales to 2050, I would classify RCP8.5 as implausible and RCP4.5 as the likely scenario.  In terms of a plausible worst case emissions/concentration scenario to 2050, the forthcoming IPCC AR6 is also using a scenario equivalent to RCP7.0.  However, given that likely projections of emissions out to 2050 are plausibly close to RCP4.5, it arguably makes more sense to use your one ‘borderline implausible’ assumptions on future hurricane activity and sea level rise under the RCP4.5 scenario.

The significance of rejecting the RCP8.5 in projections of insured losses out to 2050 is this. Any changes to hurricane activity that are dependent on increasing sea surface temperatures would be substantially muted (relative to RCP8.5).  More significantly, the greatest uncertainties in 21st century sea level rise projections are associated with possible large instabilities in the West Antarctic ice sheet arising from the highest temperature projections driven by RCP8.5. By eliminating RCP8.5, the highest sea level rise projections are eliminated.

Problems with the RCP8.5 scenario have been discussed in numerous posts at my blog Climate Etc., with references  to the primary literature as well as background information:

Citations for additional recent publications:

Amount of warming

With regards to the amount of warming associated with different emissions scenarios, projections from the CMIP5 climate models are provided in the table below [from IPCC AR5 Table SPM.2]. Substantially more warming is produced by the RCP8.5 scenario relative to RCP4.5.  The range in the projections for a given RCP scenario arises from the sensitivity of different climate models to warming from increasing emissions (primarily CO2).

It is important to understand that the temperature projections provided by the IPCC (from the CMIP climate model simulations) are not predictions of actual outcomes. Rather, they should be regarded as sensitivity analyses relative to increasing emissions. These projections neglect any changes in natural climate variability that would influence actual climate outcomes in the 21st century.

When considering scenarios of natural climate variability for the 21st century, there are reasons for thinking that the CMIP5 simulations may be predicting too much warming for the 21st century, even for the more plausible RCP4.5 emissions scenario:

  • Observed warming for the past two decades is less than the average rate of warming simulated by climate models. [link]
  • The ensemble of CMIP5 climate models do not sample the full range of likely values of equilibrium climate sensitivity to increasing CO2, neglecting the lowest 20% of the likely range from the IPCC AR5. [link]
  • Climate model projections do not include solar variability and volcanic eruptions, associated with plausible scenarios for a cooling effect in the 21st century. [link]

Specifically considering the amount of warming associated with the RCP4.5 scenario, my assessment is that temperature change  is very unlikely to exceed the upper bound of the IPCC AR5 likely range.

It is noted here that the CMIP6 temperature projections for the forthcoming IPCC AR6 are coming in warmer than CMIP5/AR5, with about half of the models having very high sensitivity to CO2.  It will be interesting to see how the AR6 evaluates this.  Topic for a blog post for another day.


AIR uses a sophisticated method to select scenarios from 100,000 stochastic simulations of individual hurricane seasons.

By 2050, AIR predicts a 15% increase of Cat 3, a 25% increase in Cat 4 and a 35% increase in Cat 5 (Cat 1 and 2 numbers are unchanged).  Not only does the AIR projection result in an increased proportion of major hurricanes, but also an increase in the total number of major hurricanes.

It is difficult to decipher exactly how these numbers were determined.  Figure 2 in the AIR report is based on Figure 7 from the GFDL statement.  GFDL’s text accompanying their Figure 7 is cited below:

“The Bender et al. (2010) study projected a significant increase (+90%) in the frequency of very intense (category 4 and 5) hurricanes using the CMIP3/A1B 18-model average climate change projection. Subsequent downscaled projections using CMIP5 multi-model scenarios (RCP4.5) as input (Knutson et al. 2013) still showed increases in category 4 and 5 storm frequency (Fig. 7). However, these increases were only marginally significant for the early 21st century (+45%) or the late 21st century (+39%) CMIP5 scenarios (based on model versions GFDl and GFDN combined). That study also downscaled ten individual CMIP3 models in addition to the multi-model ensemble, and found that three of ten models produced a significant increase in category 4 and 5 storms, and four of the ten models produced at least a nominal decrease. While multi-model ensemble results are probably more reliable than individual model results, each of the individual model results can be viewed as at least plausible at this time. Based on Knutson et al. (2013) and a survey of subsequent results by other modeling groups, at present we have only low confidence for an increase in category 4 and 5 storms in the Atlantic; confidence in an increase in category 4 and 5 storms is higher at the global scale.”

The AIR Report cited a recent publication by  Kossin et al. (2020)  which provides an analysis of satellite-derived intensities of global tropical cyclones for the period 1979-2017.  The analysis was divided into two periods: Early (1979-1997) and Late (1998-2017).  The paper’s key result  is that there is greater probability of a tropical cyclone reaching major hurricane status (Pmaj) in the Late versus the Early period, reflecting a global average increase of about 5% per decade.  When broken down by individual ocean basin regions, this increase is driven by the North Atlantic, the South Pacific and South Indian Oceans.  Notably, the West Pacific (the region with largest number of tropical cyclones) shows a substantial decrease in the probability of reaching a major hurricane.  Shown below is the main table from Kossin et al. (2020; a corrigenda to this table in the original publication was issued).

The AIR Report also cites the recent assessments from  the World Meteorological Organization (WMO) Expert Team on Tropical Cyclones (Knutson et al. 2019b). This report concluded that 2oC of warming (consistent with RCP4.5 in 2100, or RCP8.5 at mid-century) is projected to impact hurricane frequency and intensity as follows:

  1. For hurricane intensity (maximum wind speed), there is 
medium-to-high confidence that the global average will increase. The median projected increase in lifetime maximum surface wind speeds is about 5% (range 1–10%).
  2. For the global proportion of hurricanes that reach Category 4–5 levels, there is at least medium-to-high confidence in an increase, 
with a median projected change of +13%.

Author opinion in Knutson et al. (2019b) was more mixed and confidence levels lower for the following projections:

  1. A decrease of global hurricane frequency, as 
projected in most studies
  2. An increase in the global number of very intense hurricanes (Cat 4–5).

Individual experts and individual model simulations have supported scenarios as extreme as that used by AIR for a warming of 2C, although the plausibility of a large increase in number (rather than proportion) of Cat 4/5  is disputed by experts.  At this point, I would conclude that such extreme outcomes for a 2C temperature increase cannot be falsified based on our background knowledge, although they are well outside of the likely range according to the IPCC and WMO assessments.  The implausibility of the AIR scenario rests on the extreme temperature projection from RCP8.5, and borderline implausibility of a large increase in the number of Cat 4/5 hurricanes.

Missing the elephants in the room

In projecting a substantial increase in U.S. major hurricane landfalls for the period to 2050 as a result of global warming, the AIR Report ignores two elephants in the room:

  1. The historical record for major hurricanes striking the U.S. that shows elevated activity prior to 1970, when sea surface temperatures were significantly cooler.
  2. The dominant role of the Atlantic Multidecadal Oscillation (AMO) in determining overall Atlantic hurricane activity, but particularly the number of major hurricanes.

The most striking aspect of any analysis of Atlantic hurricanes and U.S. landfalls is the large interannual to multi-decadal variations.  The Figure below (from NOAA AOML) shows the yearly values since 1850, for  major Atlantic hurricane counts. While the number of major hurricanes prior to 1944 is probably undercounted, it is noteworthy that the number of major hurricanes during the 1950’s and 1960’s was at least as large as for the last two decades.

The Atlantic Multidecadal Oscillation (AMO) has a strong influence on Atlantic hurricane activity, particularly the number of major hurricanes.  Since 1995, the AMO has been in a warm phase (associated with elevated Atlantic hurricane activity.)  The previous cool phase of the AMO (1970-1994) was associated with few major hurricanes.  The previous warm phase (1926-1969) was also associated with a high number of major hurricanes, althought sea surface temperatures were substantially cooler than the present warm phase of the AMO.  [For further information, see section 4.3.1 from my Report on Hurricanes and Climate Change].

By looking at the period from 1979-2017, you can see an obvious and large increase in the number of major hurricanes (which was identified by Kossin et al. 2020).  However, any attempt to relate the large trend since 1979 to global warming must account for the large number of major hurricanes during the 1950’s and 1960’s that was at least as large as the recent numbers which  occurred in the presence of significantly lower sea surface temperatures.  Simply extrapolating the trend from 1979-2017  (and assuming it was caused by increasing sea surface temperatures) produces a future increase in Atlantic major hurricanes that is clearly unjustified when the longer data record is examined.

With regards to actual U.S. landfalls,  Klotzbach et al. (2018) have conducted a comprehensive evaluation of the landfalling hurricane data for the Continental U.S. since 1900.  The figure below shows shows the time series for major hurricane landfalls (Category 3-5). The largest year in the record is 2005, with 4 major hurricane landfalls. However, during the period 2006 through 2016, there were no major hurricanes striking the U.S., which is the longest such period in the record since 1900.

Table 6.1 shows a list of the strongest U.S. landfalling hurricanes. The strongest storm on this list occurred in 1935.  Of these 13 storms, 10 occurred prior to 1970.

While higher sea surface temperatures can improve the thermodynamic environment for hurricane intensification, Cat 4 and 5 storms can and have formed at much cooler surface temperatures in the Atlantic. With the exception of Hurricane Andrew and the Florida Keys Hurricane, each of these exceptionally strong hurricanes occurred during the warm phase of the AMO.

Scenarios to 2050

Because of the large interannual to multi-decadal variability in Atlantic hurricanes, it is very difficult to detect any signal from global warming in the historical record.

The largest increase in Category 4-5 Atlantic hurricanes is predicted by Bender et al. (2010). Owing to the large interannual to decadal variability of SST and hurricane activity in the basin, Bender et al. estimated that
 detection of an anthropogenic influence on intense hurricanes
 would not be expected for a number of decades, even assuming a very large underlying increasing trend (+10% per decade).

Given the dominant influence on Atlantic hurricanes of the Atlantic Multidecadal Oscillation (AMO), arguably the single most important factor for the next 30 years would be a shift to the cold phase of the AMO.   The timing of a shift to the AMO cold phase is not predictable; it depends to some extent on unpredictable weather variability. However, analysis of historical and paleoclimatic records suggest that a transition to the next cold phase is expected prior to 2050. Enfield and Cid-Serrano (2006) used paleoclimate reconstructions of the AMO to develop a probabilistic projection of the next AMO shift. Their analysis indicates that a shift to the cold phase should occur within the next 15 years, with a 50% probability of the shift occurring in the next 6 years.

The AMO not only influences the number of major Atlantic hurricanes, but also the preferred location of U.S. landfalls.  The average number of U.S. landfalling hurricanes in the previous cool phase of the AMO (1970-1994) is 1.24 per year, compared with 1.7 per year during the current warm phase (1995-2019). Florida and North Carolina showed markedly fewer hurricane landfalls during the previous cool phase of the AMO.

The timing of a future shift to the cold phase of the AMO remains uncertain.  Whether a future cold phase would have a comparable distribution of landfalls also remains uncertain.  However, a scenario of reduced U.S. landfalling hurricanes between 2020 and 2050 is justified by empirical evidence from the historical record in context of a possible (or even likely) shift to the cold phase of the AMO prior to 2050.  This scenario of lower U.S. landfall activity to 2050 is arguably at least as likely as the scenario put forward by AIR.

Sea level rise scenarios

The AIR report uses a 2017 NOAA Report on Sea Level Rise Scenarios for the U.S. The NOAA Report included an Extreme sea level rise scenario of 2.5 m by 2100, whose primary rationale was a paper by DeConto and Pollard (2016) that suggested increased likelihood of extreme sea level rise from Antarctic ice sheet instability.

The AIR Report selects two scenarios from the NOAA Report to bound its sea level rise estimates: Intermediate Low (0.24 m by 2050) and Intermediate High (0.44 m by 2050). The AIR Report includes local projections for New York City, Miami and Houston.  Projections from the NOAA Report (since 2000) are provided below for these four cities.  The black curve reflects observations through 2016.  Comparing the slopes of the observations with the NOAA scenarios indicates the observed sea level rise tracking most closely NOAA’s Low and Intermediate-Low scenarios.

The year 2017 (when the NOAA Report was published) arguably marked the peak influence of the DeConto and Pollard (2016) paper, with subsequent analyses backing off from this extreme scenario of Antarctic ice sheet instability to occur during the 21st century [link].  Most significantly, subsequent IPCC assessments are not producing exceptionally high projections of sea level rise, even for the RCP8.5 scenario. .

The 2019 IPCC Special Report on Oceans and Cryosphere in a Changing Climate (SROCC; Chapter 4)  provides sea level rise projections for the period 2031-2050, and 2046-2065.  To compare with the values used by AIR for 2050, the SROCC sea level rise projections are averaged here for the two mid century periods: for RCP4.5, 0.16 to 0.28 m; for RCP8.5, 0.19 to 0.33 m.  From what I have seen in the Second Order Draft, the sea level rise projections for the forthcoming AR6 are coming in lower than the SROCC values.

The sea level rise scenarios referred to in the AIR Report are quite high, with the intermediate-high sea level rise scenario being well outside the likely bounds of the RCP8.5 scenario in the IPCC SROCC Report (2019).  Relative to the more plausible RCP4.5 scenario for 2050, the AIR Report’s low end scenario of 0.24 m is near the top of the SROCC likely range, while AIR’s high end scenario of 0.5 m is well outside of the likely range even for RCP8.5; this large value is arguably implausible for RCP4.5.

So, what is the plausible worst case scenario for sea level rise by 2050? The role of instability in the Antarctic Ice Sheet on the plausible worst case scenario for 21st century sea level rise  is a very fast moving area of climate research, with much uncertainty and disagreement among experts.  However, once the high levels of warming associated with RCP8.5 are eliminated from consideration, then extreme instability of the West Antarctic ice sheet and large values of sea level rise (e,g. the Intermediate-High scenario) become increasingly unlikely, if not implausible, for  moderate rates of warming associated with RCP4.5, especially prior to 2050.


Not surprisingly, the combination of implausibly high sea level rise projections and increase in the number of major hurricane landfalls in the U.S. results in a projection of substantial increases in damage and losses.  From the AIR Report:

“The results of the analysis show that increased event frequency and sea level rise will have a meaningful impact on future damage. The growth in the number of stronger storms, and landfalling storms overall, increases modeled losses by approximately 20%, with slightly larger changes in areas such as the Gulf and Southeast coasts where major landfalls are already more likely today. The loss increases extend to inland areas as well, as stronger storms may penetrate farther from the coast.

The impacts from sea level rise, using the analysis of storm surge for New York, Miami, and Houston suggests that by 2050, sea level rise may increase storm surge losses by anywhere from one-third to almost a factor of two, with larger impacts possible when combined with increases in the number of major storms. The results suggest that an extreme surge event in today’s climate may be twice as likely to happen 30 years from now.”

While predictions for global climate change out to 2100  are  weakly constrained  and highly uncertain, we have a much better idea of the constraints on likely outcomes out to 2050. It is expected that variations in the Atlantic Multidecadal Oscillation will continue to dominate the statistics of Atlantic hurricanes for the next several decades, with any signal from global warming being difficult to discern amidst the natural variability.

The plausible worst case scenario has an important role to play in some decision making frameworks.   However, the plausible worst case scenario requires assumptions that are justified and not falsifiable based on our background knowledge.  The scenarios for climate change out to 2050 presented by AIR are based on an implausible emissions scenario that produces an implausible amount of warming by 2050.  Even if this large amount of warming is accepted as plausible, the scenario for substantially increased  numbers of major hurricane landfalls impacting the U.S. is judged to be very unlikely if not borderline implausible.  The intermediate-high sea level rise scenario in the AIR Report extends well beyond the likely range of the most recent IPCC assessment, even for RCP8.5.

Apart from the slow creep of sea level rise which in recent decades has been tracking the low end of the RCP4.5 scenario, there is little justification for expecting a noticeable increase in insured losses associated with U.S. landfalling hurricanes by 2050.



86 responses to “Assessment of climate change risk to the insurance sector

  1. Joe - the non climate scientist

    Of course the insurance companies are on board with a high risk assessment. The higher the claimed risk , the higher the insurance oversight boards will premiums to rise

  2. Insurance corporations want one thing: profits! The bigger the better.

    They will use the models that best serve that purpose. Is the model wrong?

    Who cares. By 2050 most of them will be probably dead, so they enjoy the profits today!

    I thought models were FUN entertainment before COVIDIUS…

  3. Belief in six impossible things at once must be beyond the known-unknowns and unknown-unknowns tails of the probability spectrum…

    • Judith’s Conceivable, Possible and Plausible criteria are so formidible that only a few of the greatest minds in talk radio have been able to encompass
      them in a single broadcast.

      Unfortunately the last climate communicator to do so has sadly passed away:

      • The only way I know Rush Limbaugh is that he was portrayed as a cartoon character on Family Guy so he didn’t figure very large on this side of the pond

        I have been surprised at the vitriol heaped on him by left wing commentators rather like that heaped on Margaret Thatcher by her much lesser foes, when she died


      • Hoax or no hoax, in as much as all climate change is nominally due to the sun, calling climatology a ‘science’ is a definitely a hoax since it doesn’t recognize the sun nor even clouds let alone the fact that we live in a water-world, as having anything to do with the world’s climate– they are only concerned with manufacturing a meme helpful to the Leftist educational establishment using data from UHI-corrupted ‘official’ thermometers, historical data sets and mathematical models with parameters that can be made to show anything the designer desires. In as much as none of the models can be verified and the null hypothesis of AGW cannot be falsified, I would say I would say Western science’s theory of AGW is it the least bogus if not an outright hoax and more likely a sting on the productive.

  4. Insurance is a business designed to make a high returns for investors. Proposing that there are high risks for the future is perfect gor the investment model.

    Insurance companies do no guarantee insurance prices over a long term basis. They insure for very short terms (6 to 12 months). How does climate change matter?

  5. Risk-Reward Ratio. If an insurance company gives lower rates than the real risk rate, and are wrong, the insurance company loses money. If they give higher rates and are wrong, they make more money. Decisions, decisions…

    • But if they inflate their rates a bit too much they will open the door for competitors. That’s why insurance companies hire some of the best statistical analysts in the world – known as actuaries – to balance risks and premiums. Of course the third option is to charge low premiums to get lots of customers and then refuse to pay claims. Good way to make a lot of money before being sued into bankruptcy.

  6. Likely the politics of the “green religion” has improperly influenced the report, thereby providing the insurance companies a convenient (and actuarial incorrect) way to raise rates. Follow the money. Also provides the “green religion” yet another inroad into controlling society. In this case, by skewing insurance coverage away from activities the left does not like.

  7. My formula to identify a suspicious paper: Take “Cntr F” ( for searching in the browser) and type in: “RCP8.5 business as usual”. If you find a hit, stop reading further on the garbage. It’s also a hint for every peer reviewer!

  8. Property and casualty insurance is priced and sold on an annual basis. Annual variations in the weather matter. 30 year or more forecasts of climate are irrelevant.

  9. Just found a new NOAA website to monitor droughts. I suspect the insurance companies use this data to set their rates on things like agriculture, fire risks and related human activities.

  10. Thank you, Dr. Curry! It is good that a few independent experts exist and are publishing.

    To most of the previous comments er- I had the same thought that insurance companies might have an incentive to impute higher risks. If nothing else, it might cause people to buy insurance who otherwise wouldn’t. The prices would also, presumably, be higher.

    But, I don’t know if that’s actually how the pricing actually works in the US, or elsewhere in the world. Perhaps someone who knows will pipe up.

    • Oops- forgot to hit the reply notification button, which I guess its the only way to subscribe to the reply thread. Apologies to all. Got it this time.

  11. The high fossil fueled growth Shared Socioeconomic Pathway 5 (SSP5) scenario is consistent with recent growth in global energy demand. In emission terms it is close to RCP8.5. To have high growth without the emissions requires development of cost competitive alternative energy sources.

    “Fig. 1. Energy and food demand and their drivers in the REMIND-MAgPIE baseline scenarios. Shown are global population (top row), GDP (in PPP; upper middle row), energy demand (lower middle row), and food demand (bottom row) in SSP5 over the 21st century stacked by SSP region. The figure includes a comparison with SSP1 and SSP2 for the years 2050 and 2100. SSP values are also compared with population, GDP and final energy projections in the RCP8.5 (red marker, Riahi et al., 2011) and SRES A1FI marker scenarios (blue marker, Nakićenović and Swart, 2000) and the 5th to 95th percentile range in the AR5 emissions scenario database (grey bands; IPCC, 2014). Food energy demand was not reported for these scenarios. RCP8.5 population (12.4 billion) and A1FI final energy demand (1570 EJ) are outside the plot range in 2100. The food demand categories of FAO and MAgPIE do not match perfectly, e.g., fish is not included in MAgPIE, causing a small gap between historic food demand (FAO) and our projections. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)”

  12. A few years ago I had a discussion with a senior academic at a prestigious US university about global warming. He contended that catastrophic hurricane events were increasing because of global warming. I wasn’t sure, but I said it was not likely.

    So I went back and dug out the hurricane statistics that go back to the Civil War for US landfalls. You must use landfall events because before the modern era a hurricane in the Atlantic that doesn’t reach the US would not have been seen. Lo and behold, when you plot the number of landfall events there is a slight DECREASE in landfalls. And this is true for all categories 1 thru 5. If global warming was causing stronger hurricanes, regardless of the cause of the warming, we would see an increase in landfall events. The fact that the slope is slightly negative means that hurricanes are not simply related to average air temperature.

    More recently I’ve learned that it is the DIFFERENCE between the air temperature and the ocean current temperature on the West coast of Africa that leads to hurricanes. So maybe all those temperature have been rising in tandem.

    And yes, higher risk evaluation leads to higher insurance rates. That’s why an accident or two raises your auto insurance rate. The difference here is, of course, we don’t have a large statistical base from which to calculate.

    • One would have to suspect that there is a link between SST and the PDI. Although distinguishing anthropogenic causes from internal variability – it goes without saying – remains statistically impossible.

      “This figure presents annual values of the Power Dissipation Index (PDI), which accounts for cyclone strength, duration, and frequency. Tropical North Atlantic sea surface temperature trends are provided for reference. Note that sea surface temperature is measured in different units, but the values have been plotted alongside the PDI to show how they compare. The lines have been smoothed using a five-year weighted average, plotted at the middle year. The most recent average (2011–2015) is plotted at 2013.”

      • After I posted some off the cuff remarks I found this gem from Dr. Curry:

        Special Report:
        Hurricanes and Climate Change
        Judith Curry
        Climate Forecast Applications Network
        6 June 2019

        A lot great deal of detail and understanding; about the same conclusion that nothing is happening.

      • It is extremely unlikely (>99%) that nothing is happening.


      • “This figure presents annual values of the Power Dissipation Index (PDI), which accounts for cyclone strength, duration, and frequency.”

        This is all very interesting, but of far greater relevance is the human impact of extreme weather events. When a given hurricane hits the US, lives lost is mostly counted in single digits, typically over a few days, and within a few months there is no sign that the event ever occurred. If the same storm veers in the direction of the Philippines, it’s thousands or tens of thousands of lost lives – typically over a period of weeks or months – and it can take years to fully recover. Has the hurricane increased by orders of magnitude in intensity as it crosses from the USA to the Philippines, which would account for the increased devastation? Of course not!

        A similar contrast, but in temporal terms, could be observed in the flooding of the Yangtse in China last year, which was universally spun as yet another climate change disaster by the press (i.e. the usual commentary about how the flooding had been made worse by climate change) despite only a few tens of lives being lost. None of the reports I read laid any emphasis on the miraculously low number of deaths compared to similar past events when thousands, tens, or even hundreds of thousands were routinely wiped out. Thanks mostly to China chucking vast quantities of CO2 and miscellaneous pollutants into the atmosphere, the impact of this routine flooding was reduced to virtually nothing. The net effect of all that CO2 was radically diminished flooding in every sense that matters!

        Who gives a toss whether the average energy in storms increases by ten or twenty percent over a hundred years, when that is almost irrelevant compared to other factors when it comes to human and economic impacts?

        The same plays out in sea level rise. I read some stupid article about the amount of money Miami municipal authorities are having to invest in tidal defences: some few hundred of millions over the next few years. But I then looked at the county revenues from property taxes and discovered that the annual cost of the expensive adaptation measures is only a small percentage of the average annual INCREASE in tax revenues. In other words, they should carry on building like crazy in Miami because even taking into account the cost of sea defences, they’re coming out well ahead! The same certainly applies in the case of the Thames barrier, which, however expensive, cost peanuts compared to the revenues generated by the households and businesses protected by it.

        It seems to me when it comes to weather and climate, most of the focus is on irrelevancies to the tragic detriment of things that actually matter.

      • Much more concise – the emphasis is on economic growth to provide resources to build infrastructure resilient to whatever nature throws at us from whatever cause.

      • It is extremely likely (>99%) that nothing of human cause is happening.

  13. ‘A shift to the cool phase of the AMO would arguably portend fewer major hurricanes striking the U.S.’

    Hmmm … not sure about that, the AMO should drift into neutral fairly soon after the NH summer and that might give us a clearer picture of hurricane behaviour.

  14. Take a look at the prediction of the climate models in CMIP6:!Aq1iAj8Yo7jNhBlQt8jdeBoZ9NhY
    This looks at actual annual temperature hindcast/forecast and includes today. We are told that 0.5C more is going to end the planet and yet the models differ over a 2C range right now. Chinese at the bottom end and EU at the top end – who to believe?

    • thanks for this one!

      • Hope it is useful. Just be aware that you will not find the CMRW-21 model data on KNMI. It is derived as follows:
        Average Global Surface Temperature = {30 + (-2)}/2 = 14C.
        (No “greenhouse effect” needed)
        The physics is way more complex than the equation but it is based in sound physics; not fantasy like the other 9.

        You already have the control chart that shows the operation of convective instability and convergence over the warm pools that give rise to the 30C. Sea ice formation at -2C is less controversial.

        I found another good paper that looks at the cyclic instability in the tropics:
        Figure 3 is very good evidence that my method for determining the LFC at the onset of monsoon is reliable. Figure 4 for the timing of the cyclic instability is also in good agreement with what I calculate.

      • CMRW-21 physics appears to be nonexistent – at least on the interweb. Nor do you explain what you have done with the CMIP output. There is of course a tell. The claim that models are fantasies and that there is no need for a freakin’ greenhouse effect.

        There is some maths involved – the physics are largely as competent as it gets. But the partial differential equations governing the system are nonlinear. Thus models are problematic but hardly fantasies. They are of course carefully calibrated to several empirical measures. Yet your graphs don’t seem to be?

        I take it you are calculating average global surface temperature as the mean of approximately the highest seasonal water surface temperature near Darwin and ocean heat in high latitudes at times of seasonal ice formation. Feel free to elucidate.

      • All three oceans regulate their warm pools to 30C. It is a function of convective instability and convergence. Lots of physics behind it but no fantasy of the “greenhouse effect”.

        This data is from the moored buoy at 0N, 156E when it was in the warm pool in March 2020:!Aq1iAj8Yo7jNhBad9ph_ewh61igZ
        Perfect temperature regulation – overshot to 31.5C at the onset of the monsoon in the location. Then regulating SWR and precipitation to control surface temperature within 0.5C of 30C for the period the warm pool existed at the buoy.

        It is a control process that can be observed across three tropical oceans most days of the year of any year:
        The first sign of the onset of glaciation is when the tropical Atlantic does not make it to 30C in any year; it becomes energy deficient.

        So we have a global shell that is essentially 100m thick with good heat transfer – central circumference held at 30C and smaller circumferences at the opposing ends at -2C. You can guarantee that the average surface temperature is not going to be much different to the arithmetic mean of 14C; no “greenhouse effect” needed.

        Just ask yourself – why do three separate and disparate tropical oceans all regulate warm pools thousands of miles apart to 30C. That is not the result of some delicate energy balance upset by minuscule amount of CO2. It is the result of powerful convective instability that literally blasts massive amounts of water vapour high into the atmosphere to form persistent, highly reflective cloud that can take surface level SWR from 1000W/sq.m one day to just 100W/sq.m. the next. Anyone who thinks CO2 can do anything that marthes that is entirely delusional.

      • This seems to reference a Willis theory. But first things first – there is a greenhouse effect shown in observation, experiment and from first physical principles. Then you have overestimated the cirrus cloud effect, miss the low level marine boundary layer stratocumulus anti correlation with SST and neglect ocean heat transport. And it seems more likely that the first signs of incipient glaciation will be a decline in thermohaline circulation in the north Atlantic. People are paying close attention at the 26 degree north array. I note the inauspicious contrarian polemic.

        “We compare top‐of‐atmosphere (TOA) radiative fluxes observed by the Clouds and the Earth’s Radiant Energy System (CERES) and simulated by seven general circulation models forced with observed sea‐surface temperature (SST) and sea‐ice boundary conditions. In response to increased SSTs along the equator and over the eastern Pacific (EP) following the so‐called global warming “hiatus” of the early 21st century, simulated TOA flux changes are remarkably similar to CERES. Both show outgoing shortwave and longwave TOA flux changes that largely cancel over the west and central tropical Pacific, and large reductions in shortwave flux for EP low‐cloud regions. A model’s ability to represent changes in the relationship between global mean net TOA flux and surface temperature depends upon how well it represents shortwave flux changes in low‐cloud regions, with most showing too little sensitivity to EP SST changes, suggesting a “pattern effect” that may be too weak compared to observations.”

        “Heat redistribution is one of the main mechanisms by which oceans regulate Earth’s climate. Analyses of ocean heat transport tend to emphasize global-scale seawater pathways and concepts such as the great ocean conveyor belt. However, it is the divergence or convergence of heat transport within an oceanic region, rather than the origin or destination of seawater transiting through that region, that is most immediately relevant to Earth’s heat budget. Here we use a recent gridded estimate of ocean heat transport to reveal the net effect on Earth’s heat budget, the ‘effective’ ocean heat transport, by removing internal ocean heat loops that have obscured the interpretation of measurements. The result demonstrates the overwhelming predominance of the tropical Pacific, which exports four times as much heat as is imported in the Atlantic and Arctic. It also highlights the unique ability of the Atlantic and Indian oceans to transport heat across the Equator—Northward and Southward, respectively. However, effective inter-ocean heat transports are smaller than expected, suggesting that global-scale seawater pathways play only a minor role in Earth’s heat budget.”

      • You need to learn what the “greenhouse effect” is to have a meaningful conversation. “Greenhouse effect” postulates that the surface is some 33 degrees K warmer than it would be without a “greenhouse effect”. I show that the average surface temperature simply works out to be the mean of two controlled extremes. Upper limit of 30C and lower limit of -2C.

        The radiative balance is not some delicate balance is is the result of two powerful temperature controlled processes.

        You also need two learn a lot more about convective instability and how the clear sky window narrows as sea surface temperature increases. If the surface temperature could ever get to the 33C, the sky would be in perpetual cloud but convergence limits the temperature to 30C at the point where the energy balance goes to zero.

        Another clue that might help you take some baby steps to enlightenment is to work out why the Persian Gulf has the highest SST on the planet in July and August (much warmer than any tropical ocean that has more ToA SWR) – the clue is that it has never experienced a cyclone and convective instability is a rare event.

        No I did not get the 30C from Willis. I came at the figure indecently through identifying emergent properties of the atmosphere. Judith pointed out to me some time ago that Ramanathan and Collins conceived the thermostatic control in 1994 but they had the process wrong. They only considered cirrus cloud, not the precursor and temperature precision of cloudburst. My contribution to the physics is determining that precipitable water needs to reach 30mm to create a level of free convection and at 40mm TPW, cyclic cloudburst can occur. I have also determined that the convective clod window closes when the SST reaches 33C. Also the surface radiation balance goes to zero once the SST reaches 32C. Convergence result in temperature control at 30C – very precise across all there oceans if they have the ToA SWR to reach that temperature – tropical Atlantic suffers a shortfall at certain times of the year.

        And just to be perfectly clear, convective potential relies on the radiative power of water vapour and ice high in the atmosphere for its creation. Try to reproduce the radiative power of the tropical ocean at 303K to achieve 180W/sq.m using MODTRAN. Who thinks that the atmosphere above a tropical ocean would in any way relate to the US Standard Atmosphere!

        Once you can derive the altitude of the LFC as a function of SST come back with an informed response. Unless you can do that, continue to believe in fantasies.

      • Lots of words and no meaningful data. The Earth system is so deeply and dynamically complex that only global data can mean much at all. Unless you know by observation – simplistic theory on its own doesn’t cut it – where, when and why the planetary energy dynamic is changing – it’s so much obviously contrarian kitty litter.


      • There is a reply in moderation – but it is unsatisfactory anyway. There is a greenhouse effect – it is not 33 degrees C. It is understood via experiment and, observation and obeys physical laws. The fundamental physical law is not Stefan–Boltzmann but the energy balance at TOA. The change in planetary heat content and work done is equal to energy in less energy out. By the first law of thermodynamics.

        d(H&W)dt = energy in – energy out

        Energy in changes little. Energy out changes with albedo and planetary temperature. Both change abruptly and dramatically. Only satellites will show where, when and why the planetary energy dynamic changes. In the CERES period it is largely as cloud change in the upwelling region of eastern Pacific.

    • The warming between 1950 and 2000 in models:
      You can select the one you like!

  15. I’m not sure the AIR report or any analysis of future risk and damage scenarios can capture the full import of randomness. There are many variables beyond numbers and intensity of hurricanes. Even knowing those facts, financial losses are impacted by the specific location of landfall, width of destructive winds, direction of the storm at landfall and perhaps as importantly, direction inland, topography at the coast, bathymetry, type of development, population base, etc., etc.

    I wrote elsewhere about Hurricane Michael and its damage just east of where I’m staying. Mexico Beach, a village of 1500, was hit the hardest. Half the buildings were destroyed. It is on the eastern border of a county of 150,000 people. Had Michael made a direct hit just 20 miles west, the damage would have been significantly more. Had landfall occurred 20 miles east, the damage most likely would have been significantly less, due to much smaller population and less development. Even in this one county with a 40 mile coast, scenarios of financial damage cover a wide spectrum.

    But had it gone further east, depending on the path it would have put a larger metro area at risk further inland. Or it could have impacted only rural areas.

    Randomness is tough to model. Obviously. I’ve played golf for 66 years. For the first 55 years I had 0 holes in one. In the next 7 years, I had 5. Using an average or trying to model what might happen in the future based on my history is of almost no use. Holes in one, singly or over an extended period, are random.

    Assessing financial risk is plagued with randomness perhaps more than it gets credit for.

    • UK-Weather Lass

      “Randomness is tough to model.”

      One of my first lessons in maths was the conundrum of predicting and tracking coin tosses. Being told there is every chance of an expected fifty-fifty outcome on the second toss and then never, ever, ever seeing a fifty-fifty hit again is sobering.

      Translating this conundrum into computer code is even more frustrating when you know a provided random number generator is nothing of the sort. And, of course, well before you’ve reached a sequence of thirty tosses the potential outcome patterns have already become totally unmanageable.

      And what isn’t random in life?

  16. Did the insurance industry forecast having to pay out for frozen and burst water pipes, auto accidents in the snow, and frozen windmills in Texas? You know, because it’s so unusually warm there now.

    • Lol.

      Out of the 16 days I’ve been in the Florida panhandle 6 or 7 have been in the 30s.

      It’s tough justifying driving so far just to be freezing in a new location. If the AMO flipping means even colder temperatures this place will be miserable.

  17. Climate Change is a fraud. Here are 265 Stations that show no uptrend in temperatures.

    If Catastrophic Climate Change was real, China wouldn’t be spending a fortune to build out the Maldives. Where did Obama buy his $17 million home? At sea level.

    • Maybe the Chinese actually want to put a strategic military base in the Maldives after the local government is unable to pay for their financial obligations associated with China lending them money?

      Obama will be long gone before his sea coast home is ever threatened by a rising ocean,

  18. Whichever side of the climate/hurricane debate you’re on, the stand-out thing here that others may have not touched upon is that in the grand scheme of things a 20% increase in loss **really isn’t much**. The 20% gets the headlines but it’s really not much of a headline if you’ve been working in catastrophe modelling. Sometimes our models change from version to version by 20%. The uncertainty around 50 or 100 year loss estimates comfortably exceeds 20%. 20% increase through climate almost gets lost in the wash.

    As loss – or damage – changes with the cube of windspeed (approximately, at least at the lower end of the wind spectrum), it probably amounts to maybe a 2-3% increase in hazard severity to get to 20% increase in loss.

    It’s really not a huge adjustment in building vulnerability that will counteract this 20% uplift in loss (or 2-3% uplift in hazard severity). You only need to observe the improvement in building vulnerability in Florida post-Andrew to know that we can adapt to mitigate this projected 20% loss – if it even exists by only making slight adjustment to buildings to bring down their damage curves.

  19. An energy product that is competitive in the market for energy should not require fear based acitivism against the competition. Conversely, the need for fear based activism against the competition is itself the evidence that the product is not ready for the market.

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  23. Dr. C – After this current Winter storm is over, it would be great to see a piece from you on how it happened.

    • The SSW is what started a cascade of atmospheric disruptions that resulted in the winter storm Uri. Nobody knows if SSW events are directly tied to climate change but since the artic is running 2-3 degrees warmer than the mid-latitudes I’d start there.

      • From Carbon Brief (12/31/2019)
        “The stratospheric polar vortex is a low-pressure weather system that sits around 50km above the Arctic. (There is an equivalent one over the Antarctic.) Its main feature is the strong west-to-east winds which encircle the north pole. These winds are known as the “polar night jet” because they only appear during the dark Arctic winter.

        As with the jet stream in the troposphere, the polar night jet forms a boundary between the very cold Arctic air and the warmer air over the mid-latitudes. However, if something disrupts the stratospheric polar vortex it can weaken, reverse direction and even split into two. This can trigger a sudden stratospheric warming (SSW) event where air collapses in over the Arctic, causing a spike in temperatures in the stratosphere – by as much as 50C in just a couple of days.”

        A paper (published a few weeks before the latest SSW) presents the counter argument. This seems to align with Prof. Curry’s views that ‘it’s just natural variability’ and the basis of her Stadium Wave hypothesis.

        16 November 2020
        “But predictions of a more negative Arctic Oscillation, wavier jet stream, colder winters in mid-latitudes or, more specifically, in Eurasia, and more frequent and/or widespread cold extremes have not become reality.

        Our opinion, however, is there is not enough evidence for, or physical understanding of, intermittency in Arctic-to-mid-latitude connections to allow us to disregard the simpler explanation. That is, short-term fluctuations in the coherence of Arctic and mid-latitude trends are a manifestation of internal variability, and the forced response to Arctic warming, better estimated from long-term trends and/or models, is weak in mid-latitudes.

      • Curious George

        A really great advice for insurers.

    • i know, not sure i will have time (i’m sure someone else will write this up, i will keep my eyes peeled). But i am planning something on the TX electricity failure

      • Joe _ the non climate scientiest

        JA – I am here in Dallas – I would really appreciate an unbiased account of what happened.
        So far, the media reports have not been informative – too much of someone’s agenda substituted for a through analysis.

        Early accounts (Sunday and Monday 2/14 & 2/15) blamed Windmills, later reports blamed natural gas supplies .
        Windmills have approx 24% of the electric generation capacity in Texas and with the half being frozen, that would account for approx 10% – 12% reduction in capacity. However, windmills rarely generate electricity anywhere near capacity, so its doubtfull that the windmills freezing were a majority of the problem.

        Subsequent reports were that pressure in the natural gas pipelines was insufficient to provide the necessary natural gas to power the generators. Possibly a lack of gas pressure due to lack of production at the wellhead. ie lack of supply, though that doesnt seem correct since, a large segment of the country uses natural gas for heating and only Texas / ERCOT had problems.

        Texas/ERCOT has had several times in the past using 72k-74k GW of power per hour during hot days during the summer. The reports I saw publiished, showed the entire ERCOT using approx 65K-66k GW per hour.
        In effect 8-9% below prior peaks, though the 65k was for 20 + hours vs 74kGW for just a couple hours a day.

        those are just a few observations – We await your analysis.

        Gotta run and finish my last snowman since the Gorecle said I will never see snow again.

      • As a owner of a active gas lease my #1 complaint is the sharp drop off of production with horizontal fracking. The first couple of years it’s fantastic but by year 10 I’m down to a fraction of what it was producing in 2009. It took 10’s of millions of years to sequester that gas and we will have drained out most of it by 2030. Rapid field depletion may not be seen as a problem for now but in 15 or 20 years we will wish we were more frugal in exploiting a non-renewable resource like Nat. Gas.
        Search for “fracking production decline rate Texas”

      • Joe – food for thought:
        On the other hand, coal can be stockpiled by literally piling it up outside. A generating plant can have a month or two worth of coal with no problem. Also, coal is the most regionally available of all fossil fuels.

      • Coal plants solve the problem of fuel supply in really cold weather.

      • Oil companies want, well, the oil. Nat gas is just a cheap by-product for them. Almost a nuisance. But it’s a real blessing for the rest of us.

      • jim2,
        All fracked wells show the same decline curve. It’s the physics of tight oil/gas formations.
        The short term thinking of venting and flaring of natural gas is stupid. When the Permian basin was developed they should have invested in pipelines and storage to capture that gas up front.

        PS: Wet coal stockpiles are unusable. Even when there is snow on the coal it requires pre-processing to remove the moisture content.

      • “PS: Wet coal stockpiles are unusable. Even when there is snow on the coal it requires pre-processing to remove the moisture content.”

        Since rain is common, I doubt that wet coal stockpiles are an issue. We have thinks like plastic to deal with that.

      • @jacksmith4tx “It took 10’s of millions of years to sequester that gas and we will have drained out most of it by 2030. Rapid field depletion may not be seen as a problem for now but in 15 or 20 years we will wish we were more frugal in exploiting a non-renewable resource like Nat. Gas.”

        You are terribly out of date! Do you not know that because people in the past ignored your sage advice to be frugal, production maximum was reached – as forecast by reputable bodies and experts at the time – and thereafter went into precipitous decline exactly as had been warned? This happened in each of the following years:

        1921, 1968, 1995, 2000, 2005, 2008, 2010, 2013

        Wise prophets like you often not listened to: hence the preceding crisis points that resulted the collapse of industrial civilisation as we once knew it shortly afterwards! Thank you for your 2021 + 9, 15 or 20 years numbers – I’ll add them to the list.

      • Jack – I’m familiar with the relatively steep decline curve for fracked oil and gas wells. Technology diminishes the decline for newly fracked wells over time. I was saying technology would save the day back when the Kingsmen wouldn’t shut up about peak oil. I was right. They were wrong.

  24. Curious George

    My native species is a badly misnamed “Homo Sapiens”.

  25. Judith

    Is the Texas weather Merely unusual or is it unprecedented?

    This is an account of the terrible winter of 1848 which seems to cover a similar area to the one in the reports.

    A TRAGIC EXPEDITION | Texas History and genealogy, written by those who lived it. | Frontier Times Magazine

    I am not familiar with Texas so can anyone confirm we are talking about the same area as has been hit the last few days?


    • tonyb,
      In the early 1500’s some of the Spanish explorers encountered some pretty brutal cold weather along the Gulf coast.
      Check the history of the Narváez expedition, 1528 – 1535.
      “A Land So Strange: The Epic Journey of Cabeza de Vaca”

    • A few places have tied cold records. Most didn’t. So this is hardly unprecedented

      • judith

        I agree. This is unusual , but in the historic context .i.e longer ago than the last hit by George Michael-it is not unprecedented. However that is the narrative, that this is caused by climate change caused by man.

        That unusual cold is man made rather than unusual warmth being so, is counter intuitive.

        Where are the American Historians citing these past cold events.


      • I wonder how much of this is the extreme cold, and how much may be attributed to the related ice storm, which doesn’t necessarily accompany extreme cold, and also for which extreme cold isn’t necessary.

      • Tony

        In answer to your first question about the area affected, San Luis Valley is in Central/Lower Colorado bordering New Mexico a few hundred miles to the northwest of the Texas Panhandle. So it is several hundred miles north of the latitude of the cold in say, Houston and San Antonio which are in the news. It’s difficult to know the exact temperatures in the account for that area but find it hard to believe it was a rarity in the 1800s, or prior to or after.

        Where are the historians? I guess that is a rhetorical question. But from my perspective I’ve seen hundreds of weather maps over the years with the pattern just like my link. The cold intruding into the southern interior of the US like a wedge is very common. Very cold temperatures in the northern plains (Dakotas, Nebraska) and Upper Midwest happen every winter, even with the recent warmer temperatures. Maybe the number of cold spells have diminished and the number of subzero nights has diminished in recent years but during the 1960s and 1970s that would have been the norm in January and February. The pattern of cold from interior Canada colliding with warm moist air from the Gulf of Mexico would have happened regularly during the nonexistent Holocene Thermal Maximum, the nonexistent Minoan Warm Period, the nonexistent Roman Warm Period, the nonexistent Medieval Warm Period and the nonexistent Little Ice Age. It continues in the very existent man made warm period. That collision of dry cold Canadian air and warm, moist air from the Gulf produces Tornado Alley and is responsible for the US regularly being numero uno in tornadic activity. (Here in the Florida panhandle we had a tornado 2 days ago 6 miles from us, and we are under a tornado watch as I write this. No big deal.)

        What is unusual and perhaps rare is the depth of the cold, geographically and the actual reading, all the way to the Mexican border. That would have been remarkable even 50 years ago. But not unprecedented. The word unprecedented should always be verboten since we have no way of knowing what has happened over the last million years, unless of course, you are the million year old man.

      • Ceresco kid

        When I was asking about ‘where were the historians,’ I was thinking of the professional ones who could provide context. When Judith was giving her senate? hearings, I read all the data from all those giving witness and really no one was spelling out the historic context.

        As with the current hysteria about records and ‘unprecedented’. When do the records go back to? Do they include the records we have going back to the 17800’s-still relatively recent in historic terms. The US weather Review used to provide lots of detailed information. I read many of them in the Met Office library. They date to around 1830. I don’t know if they are online


      • Tony

        A little OT but in a comment elsewhere someone remarked about getting their Buffalo robe out to provide warmth. I began to think of the Native Americans who endured the harshest of cold conditions throughout the millenia having only the most primitive protection and ability to fight the elements. The Plains tribes would have faced this weather every year. Unimaginable.

        That would be an interesting history to read.

  26. Regardless of what happens in the next 50 years
    if it gets colder or hotter
    if there are less or more hurricanes
    if there is more or less snow and rain
    if Antarctica and the Arctic grow or shrink
    If the Sahara desert gets greener or browner

    regardless of any of this, the political landscape will stay the same and the same people will keep on saying the same things. Everything that happens – no matter what it is – will justify everyone’s agenda.

    In the light of this, why even bother with predictions?

  27. If insurers raise prices based on implausible projections, would that create a market opportunity for a competitor to bet against the alarmist assessment and offer their product at a lower cost?

    • “If insurers raise prices based on implausible projections, would that create a market opportunity for a competitor to bet against the alarmist assessment and offer their product at a lower cost?”

      It would. But if the projections are accepted as authoritative, the insurance companies might move in lock step. And, as mentioned before, they do have an incentive to overprice – as long as everyone else does it too.

  28. Has it been noted that an increase in violent weather phenomena due to greenhouse gases appears at odds with the notion that inhibited tropospheric radiative energy transport is not, even partially, compensated for by enhanced convection, i.e. the prevalent model of Radiative-Convective Equilibrium?

  29. “The AIR Report ignores the ‘elephant in the room’ that is of relevance to their target period to 2050: the Atlantic Multi-decadal Oscillation (AMO). A shift to the cool phase of the AMO would arguably portend fewer major hurricanes striking the U.S.”

    The ‘elephant in the room’ is that the AMO is always warmer at least during each centennial solar minimum. Which is why the 1880-1890’s had such intense US landfall seasons. If rising CO2 forcing projects onto natural variability it should be driving a colder AMO, via a positive NAO/AO influence.

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  32. Hello,

    Do you have an internet link for the following sentence ?

    “From what I have seen in the Second Order Draft, the sea level rise projections for the forthcoming AR6 are coming in lower than the SROCC values.”.

    Thanks in advance

  33. Pingback: Dr. Judith Curry on Using Climate Risk Models that Fail Backtests to Estimate Risk – Econophysics2020

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