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Messages - BornFromTheVoid

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Arctic sea ice / Re: The 2020 melting season
« on: July 23, 2020, 03:55:52 PM »
NSIDC extent now lowest on record by 655k, and over a million km2 below the average of the last 10 years. We're 1.06 million km2 below the 2010s average, 1.98 million below 00s, 2.78 million below 90s and 3.31 million below the 80s.

9 of the last 20 melt seasons will produce a minimum below 2012, and the 10 year average gets us down to 3.45 million km2. Slowest melt, 2001, will produce the 5th lowest minimum, at 4.21 million km2.

Arctic sea ice / Re: The 2020 melting season
« on: July 23, 2020, 12:11:56 PM »
0z ECM and GFS in broad agreement on the weather to day 4/5, a variable mix of high and low pressure and a broad pattern favouring dispersion.
After that, ECM allows a deep low to take hold with some potentially stormy conditions, while the GFS produces a reverse dipole with a strong Atlantic to Pacific air flow.

06z GFS coming out now, so interesting to see where that goes

Arctic sea ice / Re: The 2020 melting season
« on: July 22, 2020, 03:56:03 PM »
8 of the last 20 melt seasons will produce a minimum below 2012 now, and the 10 year average gets us down to 3.52 million km2. Slowest melt, 2001, will produce the 6th lowest minimum, at 4.347 million km2.

Here's a Landsat 8 RGB composite of Petermann Glacier, from July 17th.

Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 08:22:19 PM »

I have a quibble with these sorts of projections: They don't take into account the patterns of melt. Virtually every season rather closely follows a few overall patterns, and virtually every melt season has the specific pattern that the slope of the line in the first half of July continues into mid- or late August. Just tagging on the melt from this point on onto the end of 2020 is not likely to capture the actual potential outcome.

I largely agree. The projections I post are simple and naive, not meant in terms of any genuine scientific pursuit. Every melt season is different - every year the ice is configured differently in terms of thickness, coverage, age, formation history. The weather is different each year too. In fact, everything is different every year. Even where slopes line up, they can be lining up for completely different reasons. No method so far is capable of capturing the eventual outcome, mine is certainly no different.

We are in uncharted territory here, but there's no harm is playing with the data a bit!

Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 04:18:58 PM »
Latest simple projection has 7 of the last 20 melt seasons causing a record low, and the 10 year average melt gives a low of 3.53 million km2. Slowest melt (2001) gives a low of 4.39 million km2.

Arctic sea ice / Re: Arctic Image of the Day
« on: July 21, 2020, 01:23:21 AM »
Something I put together earlier from the New Siberian Island.

Slightly higher res version on my twitter:

Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 12:30:43 AM »
ECM want to send some heat over the remaining thick ice at the end of the week. 2020 is relentless.

Arctic sea ice / Re: The 2020 melting season
« on: July 19, 2020, 09:43:52 PM »
What numbers do we get if we use the most konservative numbers from now and onward?

Based on the last 20 years, the slowest melt was, by far, 2001. That would produce a minimum of 4.41 million km2, 7th lowest on record.
Next slowest is 2006, which would give a minimum of 4.16 million km2, 5th lowest.

Arctic sea ice / Re: The 2020 melting season
« on: July 19, 2020, 05:42:05 PM »
Latest projection has 7 of the last 20 years beating 2012, and the 10 year average melt reaching a low of 3.56 million km2

Despite remaining in roughly 4th lowest position since the last update, the gap to the lowest volume continues to shrink.

Arctic sea ice / Re: The 2020 melting season
« on: July 18, 2020, 01:52:34 PM »
The ensemble probability maps (animated below for 120 to 192 hours out) are now showing a high risk of strong winds (>50km/h) around the Arctic from 5 days out. These kinds of maps can be more informative than looking at individual model runs when assessing the probability of storms and such.

Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 04:45:14 PM »
After the latest NSIDC extent update, we're now below the minima of 4 additional years, '82, '86, '92 and '96.

All but 2 of the last 20 melt seasons would put the 2020 minimum at least 2nd lowest on record.

The average extent loss of the last 10 years would produce a minimum of 3.64 million km2

Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 11:30:58 AM »
With the NSIDC data updated, we've seen a drop of 2.257 million km2 since June 30th, this is a record for that time period, with the next lowest being 2007 with 1.951 million. It's also a record in terms of the % dropped, 23.9% , much higher than the next largest, 20.2% in 2011. Incredible changes.

Will PIOMAS join in on the dramatics, I wonder?

Arctic sea ice / Re: The 2020 melting season
« on: July 16, 2020, 11:11:43 PM »
Attached is a gif (quite big ~9.7mb), showing the projections of the 2020 NSIDC extent using the extent losses of the last 20 years, and starting in March. Unfortunately, the NSIDC data hasn't updated since the 12th, so I'm fascinated to see how it looks now!

Arctic sea ice / Re: The 2020 melting season
« on: July 16, 2020, 11:08:10 AM »
An animation of the ADS concentration values at 5 days increments, from June 30th to July 15th.
(click to play)

Arctic sea ice / Re: The 2020 melting season
« on: July 11, 2020, 04:41:53 PM »
Latest NSDIC daily extent shows a big drop again, 176k. That's 2 mega melt weeks in a row, 2.015 million km2 lost in 2 weeks.

Below is the latest projection up to the end of September, and an animation of how that has changed over the last 4 days below that.

Arctic sea ice / Re: The 2020 melting season
« on: July 10, 2020, 03:41:51 PM »
The run of 100k+ losses on the daily NSIDC extent ended today, just barely, with a drop of 96k. The gap to the next lowest year, 2019, is now just 61k.

Arctic sea ice / Re: The 2020 melting season
« on: July 09, 2020, 06:32:21 PM »
NSIDC daily extent

11-day change is -1721
11-day average is -156

Has there ever been a series of numbers like this before? I'm too lazy to look through the historical data. I may load it all into a SQL database to run some queries.

2020-06-27  9.854
2020-06-28  9.723  -131
2020-06-29  9.575  -148
2020-06-30  9.445  -130
2020-07-01  9.262  -183
2020-07-02  9.142  -120
2020-07-03  8.942  -200
2020-07-04  8.807  -135
2020-07-05  8.648  -159
2020-07-06  8.455  -193
2020-07-07  8.276  -179
2020-07-08  8.133  -143

At 11, that appears to be the longest stretch of consecutive 100k losses. Next longest stretch seems to the the 8 days up to July 13th in 2011. A few occasions where a single day or two prevented longer streaks

Arctic sea ice / Re: The 2020 melting season
« on: July 09, 2020, 04:42:30 PM »
Latest version of the graph from yesterday. Following the extent loss of 3 of the last 20 years would put us below the 2012 minimum. Yesterday it was just 1. Animation from yesterday to delay is at the bottom.

Arctic sea ice / Re: The 2020 melting season
« on: July 08, 2020, 10:57:50 PM »
The graph below is a projection of the 2020 NSIDC daily sea ice extent, based on the daily losses since 2000, with the oldest years being lighter grey lines and most recent being darker gray. The years with the lowest minima are coloured. It also includes the date and value of all previous daily minima in circles.
Based on the projections it appears almost certain now that we'll finish in the bottom 6, but will still require and one of the largest losses on record to beat 2012. This is, of course, ignoring the conditioning of the pack, low volume and the continued forecast for high pressure.

Arctic sea ice / Re: The 2020 melting season
« on: May 11, 2020, 11:53:30 AM »
The 850 hPa temperature is somewhere away from the ice. I'm not sure of the altitude, maybe someone with more knowledge than me can provide that.

But it is the temperature adjacent to the ice that is going to impact the ice, not the temperature 1,000 feet above sea level. For the benefit of the lurkers who are reading the thread, I think it's useful to kick the tires and questions some assumptions about the magnitude of the current events.

The heat coming into the Chukchi and ESS and the high winds pushing ice through Fram is quite significant and easily understandable and acceptable. No problem.

Maintaining heat over ice for a very long distance over ice and delivering it to the surface of much of the CAB where it can impact the ice in May is a completely differently animal. Skepticism of this is healthy from a scientific perspective.

Surface air temperatures over the ice are held close to a 0C maximum due to the latent heat of fusion of ice. This is quite apparent each year on the DMI 80N temperatures. For that reason, using something like the 850hPa temperature (or the less common, 925hPa value) is useful for assessing the relative heat mass over the ice. It's far from perfect, and temperature inversions, fog and such will add more complications, but much of the time in summer, 850hPa temperatures are more useful than surface temperatures.

Consequences / Re: Global Surface Air Temperatures
« on: October 15, 2019, 01:30:42 PM »
2nd warmest September on record according to the JMA

8 warmest Septembers all in the last 8 years.

Consequences / Re: Global Surface Air Temperatures
« on: September 17, 2019, 04:30:09 PM »

Consequences / Re: Heatwaves
« on: July 26, 2019, 04:42:23 PM »

Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 26, 2019, 09:53:48 AM »
The heat from Europe is now beginning to make its way north west towards Greenland, via Iceland. You can track the movement on the 850hPa anomalies in the animation below.

By the time it arrives, as mentioned by grixm, surface temps are widely above 0C across the ice sheet, with plenty of very warm spots around the coastal fringes.

Consequences / Re: Heatwaves
« on: July 25, 2019, 08:00:10 PM »
Some records for the day

The #heatwave across Europe meant Germany (42.6 °C), the Netherlands (40.7 °C) and Belgium (40.6 °C) had their highest temperatures on record today.

Several sites including Paris, Edinburgh, Cambridge and Writtle also recorded their highest ever temperatures

Consequences / Re: Heatwaves
« on: July 25, 2019, 07:33:41 PM »
I think the Asian economies are heading towards recession (even if fake China numbers don't show it), and this may have to do with aerosol %s dropping? I can't think of another explanation for Paris beating the 1947 record by 5F.

The Met Office did an interesting live video today discussing the current heatwave, the dynamics and the role of climate change.

At about 16 mins in they mention that northern Africa has warmed about 2C over the last century, and this is where the air for the heatwave is originating, hence the ability to smash records.

Consequences / Re: Heatwaves
« on: July 25, 2019, 03:52:34 PM »
KNMI have confirmed 40C+ in the Netherlands.

UK July record has been broken too

Plenty of time for more.

Consequences / Re: Heatwaves
« on: July 25, 2019, 11:20:32 AM »
Today is the big day for records in western Europe. Temperatures already above 30C across much of Belgium, Netherlands, south east England and mid 30s around Paris.

Consequences / Re: Heatwaves
« on: July 22, 2019, 10:51:52 AM »
Looks like a lot of monthly and all time records could fall across western Europe in the coming week.
In the UK, many models are predicting temperatures of about 37C in the south east on Wednesday and Thursday, with a few models creeping close to 40C.
This is quite extraordinary, considering the July record is 36.7C from 2015 and the all time record is 38.5C from August 2003.

Arctic sea ice / Re: The 2019 melting season
« on: July 21, 2019, 10:42:10 AM »

In spite of what the weather models sometimes report, the actual temperatures in the northern CAA have been very warm over the past several days.   As discussed in previous posts, on July 14, 2019 the weather station at Alert, Nunavut hit 21C the warmest temperature ever measured north of 80 degrees Lat. 

A team of field researchers just wrapped up a 2 week trip on Axel Heiberg and reported widespread permafrost melting.  One of the researchers, professor Gordon Oz Osinski, said “in the 20 yrs since I started fieldwork in the Arctic I’ve never had such a long stretch of sun & temperatures in the teens [C].”  To find the thread, open Twitter and search #AxelHeiberg2019. 

Below is the link to the gif showing the permafrost melting.  It is definitely worth a click.  Pretty incredible sight when you consider that is happening at 79.8 degrees north latitude!

I think the crack that has opened (for a few weeks now) north of the CAA will likely be persistent, and could be significant this year.

What you're seeing in the video is likely part of what's called a thaw slump. While the number of them has increased quite dramatically in the Arctic over the last few decades, they are also just a normal occurrence in many paraglacial landscapes and have occurred in the Arctic for millennia.
They happen when layers of thick buried ice get exposed to the air. This can be by erosion from waves, rivers, or from things like heavy rain, which can cause the surface permafrost to detach. When the ice melts back, the soil on top slides down, mixes with the melt water and forms large flowing mud lobes at their front.
Here's 2 examples from my own fieldwork in 2017

Consequences / Re: Global Surface Air Temperatures
« on: July 16, 2019, 11:08:37 AM »

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 10, 2019, 09:41:11 PM »
Applied the filter, these are all 5-day avg double century drops in NSIDC, so we'll see tomorrow

Perhaps I've got something wrong, but I'm not getting those results. Are you sure the fact extent was collected every 2 days generally between 1979 and 1987 isn't messing up your stats?

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 10, 2019, 05:15:43 PM »
Neven, the daily extent drops show two consecutive double-century drops. Is the latest one a record? (Graph from Alphabet Hotel above)

Consecutive double centuries happen every now and then. The most recent was July 27th to 29th last year, with with drops of 211k and 253k.
2014 had one too, between the 27th and 29th of June, with 228k and 275k

Consequences / Re: The Holocene Extinction
« on: July 10, 2019, 12:15:51 PM »
Breaching a 'carbon threshold' could lead to mass extinction

Daniel Rothman, professor of geophysics and co-director of the Lorenz Center in MIT's Department of Earth, Atmospheric and Planetary Sciences, has found that when the rate at which carbon dioxide enters the oceans pushes past a certain threshold—whether as the result of a sudden burst or a slow, steady influx—the Earth may respond with a runaway cascade of chemical feedbacks, leading to extreme ocean acidification that dramatically amplifies the effects of the original trigger....

...What does this all have to do with our modern-day climate? Today's oceans are absorbing carbon about an order of magnitude faster than the worst case in the geologic record—the end-Permian extinction. But humans have only been pumping carbon dioxide into the atmosphere for hundreds of years, versus the tens of thousands of years or more that it took for volcanic eruptions or other disturbances to trigger the great environmental disruptions of the past. Might the modern increase of carbon be too brief to excite a major disruption?

According to Rothman, today we are "at the precipice of excitation," and if it occurs, the resulting spike—as evidenced through ocean acidification, species die-offs, and more—is likely to be similar to past global catastrophes.

"Once we're over the threshold, how we got there may not matter," says Rothman, who is publishing his results this week in the Proceedings of the National Academy of Sciences. "Once you get over it, you're dealing with how the Earth works, and it goes on its own ride.

The Paper itself

Characteristic disruptions of an excitable carbon cycle

The history of the carbon cycle is punctuated by enigmatic transient changes in the ocean’s store of carbon. Mass extinction is always accompanied by such a disruption, but most disruptions are relatively benign. The less calamitous group exhibits a characteristic rate of change whereas greater surges accompany mass extinctions. To better understand these observations, I formulate and analyze a mathematical model that suggests that disruptions are initiated by perturbation of a permanently stable steady state beyond a threshold. The ensuing excitation exhibits the characteristic surge of real disruptions. In this view, the magnitude and timescale of the disruption are properties of the carbon cycle itself rather than its perturbation. Surges associated with mass extinction, however, require additional inputs from external sources such as massive volcanism. Surges are excited when CO2 enters the oceans at a flux that exceeds a threshold. The threshold depends on the duration of the injection. For injections lasting a time ti≳10,000 y in the modern carbon cycle, the threshold flux is constant; for smaller ti, the threshold scales like ti−1. Consequently the unusually strong but geologically brief duration of modern anthropogenic oceanic CO2 uptake is roughly equivalent, in terms of its potential to excite a major disruption, to relatively weak but longer-lived perturbations associated with massive volcanism in the geologic past.

Arctic sea ice / Re: The 2019 melting season
« on: July 09, 2019, 10:08:51 AM »
Judah Cohen appears to be anticipating a gradual shift towards a neutral or slightly negative AO for the remainder of the month (as opposed to more strongly negative in recent weeks), so this suggests average or slightly above average surface air pressures generally across the Arctic ocean.
However, he is also suggesting that the NAO will remain in its negative state, which means higher air pressure around Greenland.

Looking at the anomaly charts for geopotential height, which you can roughly take as a guide to surface pressure patterns, high pressure remains around Greenland and stretching back towards the Beaufort sea, with low pressure across the Eurasian side of the Arctic.

6-10 day

11-15 day

Rather than a general period of storminess, this suggests a switch to a more dipole like patterns, which a chances of some depressions around the ESS, Laptev and Eastern side of the central Arctic ocean.
While it might not bring the exceptional heat the last 2 months, the potential for compaction and export from such a fractured pack is very high, and leaves little reason to suggest the weather will save the ice.

Warmest June daily maximum temperature on record for the CET zone in England, at 30.6C, beating 30.3C from 1976. Records going back to 1878.

These summer storms do not typically dump that much total rain.  While rainfall rates may exceed an inch per hour, they seldom last very long.  Normally, these are good for the crops, as they provide water, while cooling the air in the late afternoon.  Areas that are too wet, do not need any more.

Intense rainfall tends to produce surface runoff rather than percolating into the soil. This is especially the case if the soil is already saturated. This isn't so good for crops, and can also wash away a lot of soil, along with nutrients and pollutants, into local streams and rivers.

Consequences / Re: Global Surface Air Temperatures
« on: June 25, 2019, 01:06:58 PM »
Chart shows worlds temperature changes:

I made a somewhat similar graphic for the Central England Temperature earlier this year. It goes from 1659, top to bottom, is colour coded based on ranking, has all months and annual temperature for the last column, and includes the max and min data from 1878 onward. If you zoom in, you can see the dates and actual temperature for each month, as well as a few notable years and periods are highlighted

Some incredible record breaking temperatures going on here.

70s in Alaska, Northern Canada, Washington State Smash All-Time March Warm Records Before Winter Ends

  • Temperatures surged above 70 degrees in Alaska and northern Canada this week.
  • All-time March records were shattered in these northern latitudes.
  • Seattle nearly hit 80 degrees, their warmest day anytime from November through March.

Farther south, Tofino, British Columbia, also crushed a March record Tuesday, soaring to 24.5 degrees Celsius (about 76 degrees Fahrenheit)... It appeared this would have also set an April all-time high, there.

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 26, 2019, 05:48:12 PM »
Those February records didn't last too long. 21.2C today, earliest date for 70F.

That's the old February recorded beaten by 1.5C now. Crazy that it feels like summer in February.

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 25, 2019, 02:06:18 PM »
It's official. First ever 20C+ recorded in the UK during a winter month.

70F is the next target!

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 25, 2019, 01:32:21 PM »
Wales beat that 18.8C yesterday and climbed above 19C, which it is also doing again today.
A good chance that somewhere in the UK will record it's first ever 20C+ temperature in a winter month either today or in the next 2.

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 24, 2019, 02:52:03 PM »
18.8C today is the highest February temperature ever recorded in Wales

Possibly the warmest 24 hour minimum temperature record for the UK in February too

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 22, 2019, 08:42:14 PM »
More UK records, with 21 stations setting new high temperatures for February in the north.

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 21, 2019, 06:12:51 PM »
Scotland broke it's February temperature record today with 18.3C, beating the 17.9C recorded in 1897.

Consequences / Re: Global Surface Air Temperatures
« on: February 16, 2019, 01:03:57 PM »
JMA have January 2019 as the joint 2nd warmest on record (with 2017)

1st. 2016(+0.52°C),
2nd. 2019,2017(+0.39°C),
4th. 2015,2007,2002(+0.29°C)

Consequences / Re: 2019 ENSO
« on: February 14, 2019, 06:04:17 PM »
Synopsis: Weak El Niño conditions are present and are expected to continue through the Northern
Hemisphere spring 2019 (~55% chance).

Consequences / Re: Global Surface Air Temperatures
« on: January 12, 2019, 12:01:37 PM »
So, is the 2018 data out? How did it finish?

4th warmest according to the JMA at least

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