donsutherland1

It is horrific. Another terrible weekend lies ahead.

I agree concerning Antarctic ice melt accelerating. I was focused on the Arctic. Australia remains on a bad climate and bad policy course (still expanding coal production). It remains uncertain whether this season's historic fire season will prove to be a political game-changer there.

My guess based on what's happened from 2000 onward and the climate papers I've read is that a general decline will continue at varying rates. The average rate might slow somewhat from the most rapid average rate seen during the last 10 years, but the 2012 minimum extent figure will be surpassed during the 2020s, and maybe more than once. Arctic warming will continue with aggressive feedbacks. I don't see a plausible mechanism that might materially slow the rate at which it is warming right now, though maybe others can identify one if it exists.

Penn State climate scientist Michael Mann's op-ed from Australia where he will be conducting research: The brown skies I observed in the Blue Mountains this week are a product of human-caused climate change. Take record heat, combine it with unprecedented drought in already dry regions and you get unprecedented bushfires like the ones engulfing the Blue Mountains and spreading across the continent. It’s not complicated. The warming of our planet – and the changes in climate associated with it – are due to the fossil fuels we’re burning: oil, whether at midnight or any other hour of the day, natural gas, and the biggest culprit of all, coal. That’s not complicated either... Australians need only wake up in the morning, turn on the television, read the newspaper or look out the window to see what is increasingly obvious to many – for Australia, dangerous climate change is already here. It’s simply a matter of how much worse we’re willing to allow it to get. Australia is experiencing a climate emergency. It is literally burning. It needs leadership that is able to recognise that and act. And it needs voters to hold politicians accountable at the ballot box. https://www.theguardian.com/commentisfree/2020/jan/02/australia-your-country-is-burning-dangerous-climate-change-is-here-with-you-now And a link to commentary by Nerilie Abram, investigator at the ARC Center of Excellence for Climate Extremes and an associate professor at the Research School of Earth Sciences at the Australian National University. https://blogs.scientificamerican.com/observations/australias-angry-summer-this-is-what-climate-change-looks-like/ 2019 was Australia's warmest and driest year on record.

I believe there is a relationship. I am not aware of literature demonstrating that they are manifestations of a larger phenomenon.

Today's AO value of +3.653 was the highest such figure since December 23, 2016. Unfortunately, it was timed for January, not some month outside of winter. Moreover, since January 1950, there are only 8 prior cases where the AO reached +3.500 or above in the January 1-10 timeframe. Five of those cases went on to have a predominantly positive AO in February. 1976 was one such case. Three, however, saw a predominantly negative AO. One such case was 1983. Perhaps, because of the "sacrifice" that has been made, something closer to 1983 will play out. Hopefully, once the MJO departs from the Maritime Continent, its travel plans will exclude any quick returns there.

Unfortunately, yes.

The study indicates that on account of the expanding pool of warm waters, the MJO is spending somewhat more time in the Maritime Continent phases. This would make sense given the ocean-atmosphere-convection linkage.

A quick note on teleconnections and Washington, DC's 6" or greater January snowstorms (1950-2019): AO-/PNA+: 67% AO+/PNA-: 0% (biggest: 3.9") AO-: 80% PNA+: 87% NAO-: 67% n=12 If one broadens the pool to include 4" or greater snowstorms (n=22), the numbers change very little for all but the NAO: AO-/PNA+: 64% AO+/PNA-: 0% AO-: 77% PNA+: 86% NAO-: 55% Note: All of the 10" or greater snowstorms occurred with an AO-/PNA+

There may be reason for concern. Some recent scientific literature: https://www.nature.com/articles/s41586-019-1764-4

It's due to two major assumptions: 1. The MJO's progression away from the Maritime Continent and through Phase 6 into Phase 7 2. A weakening of the strong polar vortex. There are a number of cases where a super strong polar vortex in early January weakened with sustained blocking occurring in late January and/or February None of this is cast in stone, but there's enough reason to refrain from canceling winter (even if Ji has already done so).

The weakening IOD should reduce interference with the MJO. That should allow it to progress in more typical fashion. The forecast shift to the Maritime Continent (Phases 4-5) is real and the ridging forecast beyond 240 hours is increasingly likely to verify. Absent the MJO, that's still what one would expect given the forecast state of the teleconnections. And if things aren't miserable enough, there's the risk that the EPS weeklies could deliver another serving of misery a little later today. However, this does not mean that it is time to cancel winter. If things work out, the potential for a pattern change for colder and snowier weather could increase during late January. February might offer the best chance for meaningful snowfall in the Middle Atlantic region. We'll see, as a lot of variables are involved, but things should eventually get better all other things being considered.

The AO is particularly important for the Middle Atlantic region and the NAO also carries weight. New England does much better thanks to its higher latitude and has had significant snowstorms even when the AO was in excess of +2.000 in January. The following from my nearly daily discussion in the NYC forum holds true for the MD-DCA-VA areas: Based on the forecast strongly positive AO to start January, the probability of a significant (6" or greater snowstorm) for the major cities of the Middle Atlantic region during the first week of January is low. Since 1950, the biggest snowfall for that region when the AO was +2.000 or above during the January 1-15 period occurred during January 14-15, 1954 when Philadelphia received 3.0" snow and New York City picked up 2.0". Boston has had numerous 6" or greater snowstorms during such cases, including one 10" or greater snowstorm. Therefore, the risk of significant snow would likely be greatest over New England assuming this relationship holds (no significant offsetting variables). Some of the newer AO forecasts keep the AO at +2.000 or above through January 10. If so, that development could adversely impact Mid-Atlantic significant snowfall prospects beyond the first week of January.

A report by Goldman Sachs on climate change: https://www.goldmansachs.com/insights/pages/gs-research/taking-the-heat/report.pdf

One shouldn't be surprised that Heller, who has no scientific background, would imply that the winter freeze suggests a healthy Arctic sea ice situation. The difference between the 12/23 extent and minimum extent is largely the result of a very low minimum figure. According to Heller's logic, 2012 would have been seen as a fantastic year, as sea ice extent increased by nearly 8.7 million square kilometers by December 23. Of course, 2012 saw a record low minimum extent figure of just under 3.2 million square kilometers. In fact, the 12/1-23 average of 11.144 million square kilometers is the 3rd lowest on record and is nearly 3% below the 2000-19 average. This is not a healthy Arctic sea ice situation. If multi-year "old" ice were increasing, that would be newsworthy. The annual refreeze in 2019 is not.

Thanks for the kind words and Holiday wishes. I hope your family and you have a great Holiday season.

There's a fallacy that complexity of making weather forecasts at extended ranges means that climate forecasts years out are essentially not possible to make. A closer look is in order for purposes of a quick sketch. Take for example, New York City (Central Park). Let's say one is seeking to forecast the high temperature on January 1, 2020. The highest maximum temperature on record is 62°, which occurred in 1966. The lowest maximum temperature on record is 10° from 1918. The 0z GFS forecast a high of 36°. The historic range is 1.4 times the forecast high. Finally, let's say one is seeking to forecast the 2020 annual mean temperature. The warmest such reading was 57.4° in 2012. The coldest such reading was 49.5° in 1875 and 1888. Since 2000, the mean has averaged 55.7°. If one uses that estimate, the range of error is just under 0.15 times the estimate. That latter situation is the type of situation one is dealing with when it comes to making climate projections. Thus, the fallacy of synoptic complexity's precluding climate forecasts does not apply. When it comes to climate (and climate change) there are widely-established drivers of climate: solar and greenhouse gases are among the most important. Therefore, if one gets the forcings right, one should get a reasonable projection of the climate. Well, that's exactly what the research shows. Climate models have proved skillful. Retrospectively comparing future model projections to observations provides a robust and independent test of model skill. Here we analyse the performance of climate models published between 1970 and 2007 in projecting future global mean surface temperature (GMST) changes. Models are compared to observations based on both the change in GMST over time and the change in GMST over the change in external forcing. The latter approach accounts for mismatches in model forcings, a potential source of error in model projections independent of the accuracy of model physics. We find that climate models published over the past five decades were skillful in predicting subsequent GMST changes, with most models examined showing warming consistent with observations, particularly when mismatches between model-projected and observationally-estimated forcings were taken into account. https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL085378 Key takeaway: Climate should not be viewed through a synoptic lens. Finally, the physical properties of carbon dioxide are well-established. There's no serious scientific debate on that matter. Therefore, it should make little difference whether carbon dioxide is released through natural mechanisms or if human activities release carbon dioxide. The molecules should behave in the same fashion, not follow different rules depending on whether they were emitted into the atmosphere via volcanic eruptions or the burning of fossil fuels.

It won't melt immediately and could take centuries to do so. Nevertheless, it appears that humanity is committing itself to a course that could lead to that outcome given little or no response to the need to reduce greenhouse gas emissions (projected to have increased another 0.6% this year). The latest Arctic Report Card provides a glimpse of what is currently happening in the Arctic. https://www.arctic.noaa.gov/Portals/7/ArcticReportCard/Documents/ArcticReportCard_full_report2019.pdf

Sea ice melt doesn't raise the sea level by itself. It does make an indirect contribution as a feedback mechanism that is accelerating Arctic warming. That warming affects the Greenland ice sheet. Greenland's melt, which has accelerated greatly over the past few decades, has been a key driver in rising sea levels.

Young ice melts fairly fast. It's the ice melt over the summer that has a large influence over how much of the incoming solar radiation is reflected and how much is not. Declining summer sea ice is playing a large role in Arctic amplification (as it is a feedback that amplifies the ongoing warming already underway). That's a major reason why Arctic warming has exceeded the rate of global warming, especially in recent decades.

Australia's Bureau of Meteorology reported regarding yesterday: Based on preliminary analysis, yesterday, Australia recorded its hottest day on record. The nationally-averaged maximum daytime temp was 41.9 °C exceeding the record set on Tuesday, 40.9 ºC. 40.9°C is 105.6°F. 41.9°C is 107.4°F. The highest temperature anywhere in Australia yesterday was 47.7°C (117.9° F) at Birdsville Airport. The national December record is 49.5°C (121.1°F), which was set on December 24, 1972 at Birdsville Police Station. Australia's hottest temperature on record is 50.7°C (123.3°F), which was set on January 2, 1960 at Oodnadatta Airport.

It's a difficult situation. Externalities e.g., the cost of carbon emissions and their consequences, aren't captured in the pricing mechanism of fossil fuels. That's part of the reason at least some economists favor a carbon tax. In addition, certain governments have little or no meaningful commitment to addressing the great challenge of climate change (or even recognition of the science). Yet, the time left to avoid making what amounts to an almost irrevocable commitment via emissions to temperature increases above 2.0 degrees C or 1.5 degrees C is shrinking.

Thanks for this information. The 12/13-16 data has now been pulled and replaced by "M." Given the temperatures at Sitka, I suspect based on what you found and the lower temperatures there than a few days ago, the sensor was, in fact, malfunctioning.

I don't think such a model is practical given the risks that such power could be abused given human nature as it is. However, the issue of ignorant leaders or those who put narrow interests (e.g., Russia and oil) ahead of even serious global challenges are a real problem.

I believe I was quoting Vice Regent. We agree about living in a more sustainable way. The former almost certainly won't be broadly supported. The latter could and should be.