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... “It’s deeply ironic that the US state most vulnerable immediately to climate change impacts will host a meeting at which global leaders will be forced by the US to largely ignore the topic”
In summary, neither our model projections for the 21st century nor our analyses of trends in Atlantic hurricane and tropical storm activity support the notion that greenhouse gas-induced warming leads to large increases in either tropical storm or overall hurricane numbers in the Atlantic. While one of our modeling studies projects a large (~100%) increase in Atlantic category 4-5 hurricanes over the 21st century, we estimate that such an increase would not be detectable until the latter half of the century, and we still have only low confidence that such an increase will occur in the Atlantic basin, based on an updated survey of subsequent modeling studies by our and other groups. A recent study finds that the observed increase in an Atlantic hurricane rapid intensification metric over 1982-2009 is highly unusual compared to one climate model’s simulation of internal multidecadal climate variability, and is consistent in sign with that model’s expected long-term response to anthropogenic forcing. These climate change detection results for rapid intensification metrics are suggestive but not definitive, and more research is needed for more confident conclusions.https://www.gfdl.noaa.gov/global-warming-and-hurricanes/
...attorneys with the Sierra Club stumbled upon this tidbit:https://earther.gizmodo.com/there-is-not-a-climate-crisis-trump-administration-spo-1838444325/
“The BLM does not agree that the proposed development is inconsistent with maintaining a livable planet (i.e., there is not a climate crisis). The planet was much warmer within the past 1,000 years, prior to the Little Ice Age, based on extensive archaeological evidence (such as farming in Greenland and vineyards in England). This warmth did not make the planet unlivable; rather, it was a time when societies prospered.”
This text was included five times in this section of the final environmental impact statement in response to public comments legal group Trustees for Alaska submitted. All the All group’s comments revolved around the role drilling in the Alaskan refuge could have in making climate change worse.
This is the first time that the Sierra Club and its partners have identified the use of such blatant climate-denying language in an official federal environmental analysis. Government officials, including Environmental Protection Agency Administrator Andrew Wheeler and even President Donald Trump, have said such things before, but an environmental impact statement is more than words. It’s the legal support for a project. ...
The field work was performed in the Barents Sea, and the main focus of the paper is on wave processes in the MIZ. A model of wave damping in broken ice is formulated and applied to interpret the field work results. It is confirmed that waves of higher frequencies are subjected to stronger damping when they propagate below the ice. This reduces the frequency of most energetic wave with increasing distance from the ice edge. Difference of wave spectra measured in two relatively close locations within the MIZ is discussed. The complicated geometry and dynamics of the MIZ in the North-West Barents Sea allow waves from the Atlantic Ocean and south regions of the Barents Sea to penetrate into different locations of the MIZ.
Last month, I wrote at the end of the PIOMAS update:QuoteFrom what I've seen on the Arctic Sea Ice Forum, written by commenters I've known for years and highly respect, my gut feeling says this year won't be able to break the 2012 records.
But for weeks now, I've been thinking of those prophetic words uttered by Peter Wadhams, back in 2007: 'In the end, it will just melt away quite suddenly.' I don't think all of it will melt away quite suddenly in coming weeks, but maybe more than one would expect just looking at the data.
This year is a great test that will tell us a lot about the importance of melting momentum.
To be honest, I expected a clearer melting momentum signal during this final phase of the melting season. Melting momentum took off slower than years like 2012 and 2016, but when it did take off, it was fireworks (see June 2019, one hell of a month). David Schröder's melt pond fraction maps, the SMOS pixel chart, the compactness charts, the Albedo-Warming Potential graphs, the snow cover graphs, more and more they were pointing to a massive build-up of melting momentum. On top of that, PIOMAS was showing that this year was very competitive volume-wise, and for five months in a row, 2019 was in the top 3 when it came to temperature records (August coming in lowest on record):
It was clear that the spell of extremely sunny, warm weather was ending during August. That, to me, was the great test for my melting momentum theory. Weather conditions switched, but for a week or so extent loss was keeping up with 2012's pace, despite the boost provided by the GAC. But then halfway through the month, things slowed down to a crawl after all (see red trend line):
So, what happened? Of course, there was a cyclone that was in a perfect position to disperse the ice, but there was so much weak ice that in my view, momentum should have gone on for a while longer.
There are two possibilities:
1) There wasn't as much melting momentum as I assumed.
2) Melting momentum is less important than I think it is.
As said, it took a while for melting momentum to get going. Timing is of the essence when it comes to breaking melting season records. May was actually very sunny this year, but most of the radiation coming from a Sun at a still low angle, got bounced off the pristine white ice. It may sound counterintuitive, but before the real melt ponding gets going due to open skies, cloudy weather is actually worse for the ice, because with clouds comes humidity and the clouds also block outgoing radiation. This can cause the snow on top of the ice to melt just a tiny bit, deforming the structure of the snow, making it more prone to melt when the sun starts to shine in earnest. 2019 came short in this respect, as evidenced by visual inspection of satellite images. Never mind the fact that the 2018/2019 freezing season was much less spectacular compared to the previous three winters, when it comes to temperatures and extreme weather conditions.
I'm still convinced that without a decent amount of melting momentum no records will be broken. That's why in years like 2016, 2017 and 2018 it was possible to announce at an early date that the 2012 record was safe. But conversely, a massive amount of melting momentum doesn't guarantee records either. Initial ice conditions and late stage weather obviously play important roles as well.
Maybe I'm emphasizing melting momentum too much, but I still feel kind of vindicated by recent developments on the extent front. Over the last week, just a small amount of weather conducive to melting has helped nudge 2019 below the 2007 and 2016 minimums, with quite an impressive run of daily drops. Tomorrow or the day after, the 4 million km2 mark could even be breached. I always thought that this year would come in second whatever would happen, and it looks like it has:
Either way, after almost 10 years of blogging, I'm now clearly seeing the contours of that first year when ice-free conditions will be reached (in other words, an ice cover smaller than 1 million km2, which amounts to ice-free for all practical purposes). It is preceded by a freezing season similar to that of 2015/2016, starts with the melt onset 2012 saw, builds up the massive melting momentum of 2019, and ends with the crazy weather of 2016. It makes me shudder to think what the satellite images will look like then. It may take more time than most cryospheric scientists think it will take, but unfortunately, that's not much of a comfort.
The ingredients are there, AGW is the cook.
September 11th, 2019:
4,110,564 km2, a drop of -39,332 km2.
2019 is now 2nd lowest on record.
(2007, 2012 & 2016 highlighted).
Dorian was also among the longest-lasting named storms, Klotzbach said.https://insideclimatenews.org/news/07092019/hurricane-dorian-record-climate-change-bahamas-north-carolina-gulf-stream
As of Friday evening, it had been a named storm for more than 13 days, nine of them as a hurricane.
"It's quite unusual for a hurricane to remain a hurricane for as many days as Dorian has," said climate scientist Michael Mann....
...
Dorian May Have Influenced the Gulf Stream
It also looks like Dorian may also have influenced the Gulf Stream, the strong ocean current that brings warm water from the Gulf of Mexico into the Atlantic Ocean, possibly contributing to localized coastal flooding.
An undersea monitor near Miami indicated that Dorian might have slowed the speed of that current, with powerful winds pushing against it, along with a disruptive underwater churn. A slower Gulf Stream can cause the surface of the ocean to rise by several inches to a foot or more, said Tal Ezer, an oceanographer at Old Dominion University in Norfolk, Va.
That would underlie any storm surge, he said, and the effect can linger for days as it did in 2016 in Norfolk with extended sunny weather flooding the aftermath of Hurricane Matthew, whose path was similar to Dorian's. He said he's looking for that to happen in the coming days.
"After the hurricane disappears, streets remained flooded," he said. "The drainage system was blocked and couldn't drain the rain."
Yep, I’m alive. Made it to Nassau. #Hurricane #DORIAN: By far the most intense cyclone I’ve witnessed in 28 years of chasing. Thought I was playing it safe by riding it out in a solid-concrete school on a hill in Marsh Harbour. Thought wrong. ...https://threadreaderapp.com/thread/1169009558167142402.html
I'm not sure if things will get ugly as the low will be a cold oneHi Paul. Your second name isn't Beckwith by any chance? That would be an honor!
... I think these predictions get updated automatically and if I understanding correctly most of them predict Dorian to reach Nova Scotia in 5/6 days while still being near a cat1/ cat2 hurricane?
That is rare, isn’t it?
Nice. Didn't realise you could drag the base layers and have semi transparent modis over bathy.Yesterday I compared 2012 ice cover with this year on the same date. This tool makes it easy to compare both years, and I don't see any way how we could catch up to 2012 without an apocalyptic storm.
https://go.nasa.gov/345rHxN
No gifs with transparency though
Connecticut is developing risk zones more than 3x faster than safer locations
Delaware, Mississippi, New Jersey, Rhode Island are developing risk zones more than 2x faster than safer locations
Maine, New Hampshire, and South Carolina are developing risk zones faster than safer locations
New Jersey, Florida, and North Carolina have allowed the most homes built in risk zones, more than 9,000 since 2010
24 cities—including New York, Tampa, Virginia Beach, Charleston, and Galveston—have allowed at least 100 homes built in risk zones since 2010
Have anyone noticed that the whole arctic ice is rotating right now under not strong storm effect. The ice melt in north CAA and north greenland seems to speed up because of ekman pumping by such a great ice pack rotating? Of course not !There may be some upwelling in places but there doesn't appear to be much rotation of the pack recently along the north CAA/Greenland coast.
Wipneus, a question popped up and i realized I did not know the definitive answer. For the regional PIOMAS volume data, do you use the NSIDC map as I had always assumed, or the CT map that you use for the AMSR2 data?
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