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Messages - Phil42

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1
There is currently a situation unfolding in Bern (capital of Switzerland) which I am afraid could lead to a wave of repression against environmental protestors that this country has not seen before. I couldn't really find english coverage about the situation except for this article.

A wide alliance of environmental groups (climate strike, extinction rebellion and many more) have set up a camp on the parliament square early monday morning to increase pressure on our politicians to finally act. Discussions about how to "deal" with them heated up fast and right-wing politicians call for very hard measures to remove them. At the moment they are still there. Police presence is increasing by the hour. Police has already used tear gas and rubber bullets on a nearby pro-asylum-protest without any apparent reason. The atmosphere is Bern is tense as the camp is right in front of the federal building and all the politicians have to say something too.

On a side note, in the city I live in someone got sentenced to 8 months of prison for simply attending an anti-fascist protest. The levels of state repression are getting to a new level in this country. I am afraid this will continue with the current climate camp.

My full solidarity goes to all people that are currently there. I hope the police abstains from using violence against peaceful protestors for once, but my hopes are low. I will probably update again in a few days about what happened.

(I didn't really know where to post this, I hope this thread is the right place)

2
The rest / Re: George Floyd murder and blowback
« on: September 21, 2020, 08:48:38 PM »
... Does anyone else have information on the incident wiki described, or any other similar incidents?

I am going to assume that you ask in good faith and simply don't find any sources about wili's described and similar incidents. That said, it is really not hard not find information / videos
/ stories / articles of (especially US) police violence. I will list some sources that I found in a quick search. Trigger warning: Some footage may contain extreme police violence / NSFW content.

Videos:
https://www.reddit.com/r/2020PoliceBrutality/top/
https://twitter.com/greg_doucette/status/1266751520055459847
https://twitter.com/trevortimm/status/1268621018857213954?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1268621018857213954%7Ctwgr%5Eshare_3&ref_url=https%3A%2F%2Fwww.theguardian.com%2Fus-news%2F2020%2Fjun%2F06%2Fpolice-violence-protests-us-george-floyd

Articles:
https://www.theguardian.com/us-news/2015/dec/31/the-counted-police-killings-2015-young-black-men (2015)
https://www.theguardian.com/us-news/2020/jun/06/police-violence-protests-us-george-floyd
https://www.theguardian.com/us-news/2020/jun/16/its-not-about-bad-apples-how-us-police-reforms-have-failed-to-stop-brutality-and-violence
https://edition.cnn.com/2020/06/08/us/us-police-floyd-protests-country-comparisons-intl/index.html
https://edition.cnn.com/videos/us/2020/08/14/gun-violence-black-community-police-brutality-eg-orig.cnn
https://www.aljazeera.com/indepth/features/lost-eye-price-protesting-police-brutality-200620215047122.html

Now, I haven't watched all the videos and fully read all the articles myself. I just wanted to provide some links for people that have a hard time getting into this topic. Imo, to deny that police brutality (especially against PoC) is a huge problem, one has to actively close both eyes.

3
Consequences / Re: Temperature records (data)
« on: September 16, 2020, 04:12:53 PM »
Thank you Niall for the clarification. I understood it the same (wrong) way as you described. I have edited my post above to make it more clear. Fact checking is important.

4
Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: September 16, 2020, 10:24:26 AM »
Some anecdotes from Switzerland

It has been an interesting summer here. An mentionable observation I made was that people in general (including me) would describe this summer as "average" or "normal" in regards to temperature. But in reality it has been one of the 10 hottest summers ever recorded in the country. But since it was cooler than 2016, 2018 and 2019 it actually didn't feel that extreme. I think that's a very good example that our feelings of what is "normal" are shifting rapidly with the rising temperatures. This is just an anecdote, but I wouldn't be surprised to hear similar stories from other parts of the world.

Another thing that happened was that the highest alert for severe weather was issued for the first time in 15 years. Despite the summer being slightly below average in rainfall, we have seen some very intense rainfalls in the end of August causing floods in the south. This is consistent with a trend too here: less rainfall in summer, but when it rains, it pours.

And now, there was this mid-September heatwave gripping Western-Central Europe. September records broken in several stations across multiple countries. Here in CH, the station in Fahy (596m above sea level) has set a new september record of 29.9C. The heatwave doesn't get that much attention in the media, which is kind of surprising to me since the anomalies are up to 15C above normal. But then again, with the increasing number of heatwaves they feel more and more "normal" every year.

There hasn't been anything too extraordinary happening, but everything is just consistent in the trend of everything getting warmer. More heatwaves, glaciers melting, fish dying and ... nothing changes.

5
Consequences / Re: Temperature records (data)
« on: September 16, 2020, 09:19:53 AM »
Same heatwave, another day, more records broken...

From https://twitter.com/ScottDuncanWX/status/1305969477545267203

Quote
Heat records dropping left, right and centre.

Hottest September day on record for Belgium 35.4 °C. Long standing records (over 90 years) getting smashed in the Netherlands.

Reminder: we are 2 weeks from October.

6
Arctic sea ice / Re: The 2020 melting season
« on: September 15, 2020, 11:59:22 AM »
I think especially at this point in time where the melting season turns to the freezing season your graphic is incredibly useful BFTV. Because usually there is freezing and melting at the same time in different regions which the raw extent number can't describe. But your graphic/animation gives a clear overview where it is happening. Thank you for making them, especially now.

7
Consequences / Re: Temperature records (data)
« on: September 14, 2020, 11:52:26 PM »
From https://twitter.com/ScottDuncanWX/status/1305604736671010816

Quote
We have just witnessed the hottest September day in France (on a national level) since records began.

Over 230 monthly station records were broken today alone. Some of these records go back nearly 150 years.

Hotspot today was Orthez at 37.9 °C.

France just recorded the hottest September day (average of max temperature of all stations across the country). Note that the single highest recorded September temperature record hasn't been broken (as Niall has correctly mentioned 2 posts below).

8
Arctic sea ice / Re: 2020/21 Freezing Season Predictions
« on: September 10, 2020, 07:28:08 PM »
Not a very bold prediction given the state of the ice, but I predict a record or near-record late refreeze of the Kara and Laptev Sea. My reasoning behind this is because those two seas...:

a) had a very early complete melt-out this year. The Laptev Sea broke the record by about 2 weeks, the Kara had (eyeballing) a tied record-early melt-out with some other years. This can be seen in Attachment 1 (graph from here).

b) were exposed to very high temperatures compared to normal. Throughout the whole summer (and also a long time in spring) these areas recorded very high temperature anomalies. Because of the early melt-out, this additionaly means that during a long time period it was open water exposed to those temperatures. Here are the temperature anomalies for May, June, July and August.

c) are expected to keep being exposed to really high temperatures in the coming days, as can be seen in the 7-day forecast.

I think all these factors put together make a record-late refreeze possible or even likely. Of course cold, clear weather with little wind in October could change this outlook.

9
Arctic sea ice / Re: The 2020 melting season
« on: July 07, 2020, 12:20:32 AM »
Some big cracks appearing in the Perry Channel today, indicating the start of the collapse of fast ice in that region. Looking at past years on WorldView, this is not unusual for this time of the year. Still something to keep an eye on given the overall state of the ice pack.

10
Consequences / Re: Temperature records (data)
« on: February 11, 2020, 08:53:36 AM »
That website is an amazing collection, thanks a lot for that link, Tor.

11
Consequences / Temperature records (data)
« on: February 10, 2020, 01:12:43 PM »
Hello ASIF, I had this idea for a new thread with the specific purpose of keeping track of temperature records (both high and low). I haven't found a similar existing thread, but if one exists, please just remove this one.

With temperature records tumbling around the globe, I think it would be interesting of having a record (even if very incomplete) where and when new records are set. I think it would be best to limit this thread to purely data posts, and leave away big discussions (like the ASI extent data thread). Also whenever possible it would be good to provide information about the temperature that was measured (in °C or °C/°F), when (date) a record was set, where (weather station / town / country) it was set and what kind of record it is (monthly / all-time / ...). Also a source would be helpful.

To start the thread I'd like to go back to the Europe summer 2019 heatwave(s) were several country-wide all-time records were broken (source):
  • France: 46.0C in Vérargues on 28th June 2019
  • Belgium: 41.8C in Begijnendijk on 25th July 2019
  • Germany: 42.6C in Lingen on 25th July 2019
  • Luxembourg: 40.8C in Steinsel on 25th July 2019
  • Netherlands: 40.7C in Gilze en Rijen on 25th July 2019
  • United Kingdom: 38.7C in Cambridge on 25th July 2019

On a more recent note, it has been reported that the all time high for the whole continent of Antarctica has been broken with 18.3C at the Esperanza Base on 6th February 2020.

<edited title; N.>

12
Consequences / Re: Effects of Climate Change on the biosphere
« on: January 17, 2020, 10:45:08 AM »
The linked article describes one element in the chain of biosphere disruption that a changing and warming climate brings with it. I'd like to point out the chain reaction that happened and is still happening in Australia, and to a certain extent in pretty much every part of the planet:
To oversimplify it, climate change contributed to the long-term weather pattern that lead to a big drought on parts of the continent, which then lead to the precarious fire situation and huge bushfires. The bushfires in turn lead to air and ground pollution through smoke and ash emissions. The rain happening now causes the river level to rise and washes the ash into the water, causing massive fish die-offs. While it is the ash and oxygen deprivation that ultimately killed the fish, I would argue that climate change is to blame for it, even if it only played an indirect role.

This chain will continue due to the disruption in the biosphere and affect other species. Similar and other climate change related biosphere distruption chains will happen in other regions.

Hundreds of thousands of fish dead in NSW as bushfire ash washed into river
Quote
The statement said: “The suspected cause of the incident is poor water quality leading to low dissolved oxygen. Rainfall events are adding ash from the extensive bushfires throughout the region into local catchments, as well as other organic matter and sediment. This can cause rapid drops to oxygen levels in the water.
Quote
He said there was a precedent for understanding the long-term impacts of an event such as this: major bushfires in 1939 had caused ash to run into the Lachlan River, and “the fish never recovered”.
https://www.theguardian.com/world/2020/jan/17/hundreds-of-thousands-of-fish-dead-in-nsw-as-bushfire-ash-washed-into-river


13
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: November 19, 2019, 08:18:07 AM »
Just a quick question that shouldn't interrupt any discussion.

In the Sentinel images in the "PIG has calved" thread, there are always dates on the images displaying from when they are. How does one turn those date labels on in the Sentinel-hub EO-Browser?

14
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: October 30, 2019, 08:06:16 AM »
I attach three tables which show the number of days sea ice extent has been below 5M, 6M and 7M km2 around the minimum in a year.
  • 2019 extent was < 5M km2 for 64 days, which is the second highest amount, just 1 day behind 2012.
  • 2019 extent was < 6M km2 for 86 days, which beats the old record of 77 days set by 2007 & 2012 by a big margin.
  • 2019 extent was < 7M km2 for 100 days, which is the tied record together with 2016.

15
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: October 01, 2019, 09:30:29 AM »
Some data about September 2019:

The first image shows the lowest average September sea ice extents. September 2019 ranked 2nd behind only 2012 with an average extent of 4'154'852 km2.

The second image shows the ranks of the average sea ice extent of each month 2007-2019 (lowest = rank 1).

The third image shows the extent change from beginning of September to the end of September. 2019 had the 11th lowest change with a small gain of only 159'699 km2.

16
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: September 23, 2019, 08:35:24 AM »
I'd like to join in thanking gerontocrat, Juan, Alphabet Hotel, and all other contributors for their work. It is so much appreciated.

Also here is a very (un)interesting table which finally received a second row.

17
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: September 18, 2019, 09:31:24 AM »
According to the JAXA-Dataset, to date 2019 has:
  • 49 days of being lowest
  • 141 days in lowest 2
  • 162 days in lowest 3
after 260 days having passed this year.

18
Arctic sea ice / Re: Arctic Image of the Day
« on: August 15, 2019, 11:24:13 PM »
Thanks a lot for the very informative answers and images.

19
Arctic sea ice / Re: Arctic Image of the Day
« on: August 15, 2019, 10:38:12 PM »
I was randomly looking at some landscape in the CAA in the Sentinel-hub and found this in the North of Devon Island (exact position can be seen in the bottom right of the picture). Unfortunately I didn't find the name of this glacier.

What are my eyes seeing here? Did the glacier carve a tunnel through the mountain or are those two completely seperate glaciers?

https://apps.sentinel-hub.com/eo-browser/?lat=76.3746&lng=-91.8694&zoom=12&time=undefined&preset=1_TRUE_COLOR&datasource=Sentinel-2%20L1C

20
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 31, 2019, 09:20:26 AM »
Interesting to note that 30th July 2019 is the first ever day in July where JAXA extent falls below 6M km2. Before, the earliest date was 3rd August 2012. So this record has been beaten by an impressive amount of 4 days.

21
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 01, 2019, 09:04:02 AM »
Here are the tables for the extent average in February 2019. Average extent was at 13'807'922 km2, which is:

- 7th lowest in recorded history
- 27'009 km2 above the 2010 average (including 2019)
- 405'331 km2 above the record year 2018

The second image shows the rank of average extent for each month since 2011, whereas 1 means lowest.

22
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 01, 2019, 08:53:26 AM »
Here are the highest extent losses in this particular time period from Feb 22nd - Feb 28th.

For reference, the highest gain in the same time period was +371'783km2 in 2005.

23
The politics / Re: The Empire vs Venezuela - News and History
« on: February 22, 2019, 10:56:15 AM »
...
I am truly amazed by the spread of socilaism in the West especially amongst the youth. It can only happen to those who did not live in a totalitarian-socialist/communist regime. I did. I know how terrible it is and why it does not work. We had a joke: "Introduce socialism in the Sahara and soon sand will be in short supply". These regimes ALWAYS destroy human dignity, lead to opression, suffering, and lowered living standards. I can not comprehend how anyone can take the side of Maduro (Chavez).
...

Since I am in that exact group of young people who fight for socialism I think I should reply to this. And I don't reply to attack you, I just want to give you an insight of why I (and many many more especially in the youth) hold those beliefs.

I was born in this world which is run by an untouchable elite class, which has - during the last several decades - accumulated enough wealth (which in a capitalist system is power) to have total control over the life of the lower class, since money is something you need to survive in capitalist society. They have done this by exploiting people and the planet for the sole sake of profit. Since they are also the ones that are profiting from the status quo, they put a lot of effort into maintaining it. Therefore, nothing will fundamentally change (by which I mean that whoever is in power in this system still has the main goal of accumulating profit and staying in power).

Now, as you might understand, I don't like this. I don't like growing up on a planet that I will most likely see collapsing ecologically and economically. I don't like it that my life and future is controlled by same ultra-rich old men who are responsible for that and don't feel any effects of what they are doing to the people and the planet. And what I despise the most is that I have absolutely no ability to change that, since the capitalist system is built in a way that it can always survive by giving more and more power to the elite and smash every movement which intends to build a society without those classes through propaganda, sanctions and repression.

It's really not cool to look into a future where more and more people will suffer. And instead of collaborating and working together to fix the issues we face, I see leaders embracing nationalism and encouraging individualism. The "Fuck you I got mine" mindset is ultimately rooted in capitalism, and this just has no place if we want to keep this planet alive.

What I don't understand is why the majority of people keeps defending a system that is knowingly, actively and inevitably destroying lives, our planet and our future.


This went pretty off-topic sorry, but I just wanted to give an insight to El Cid. Now back to topic.

24
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: February 14, 2019, 09:39:31 AM »
For anyone who is like me and thought this increase is very weird.

I checked some numbers and while a century increase this late is unusual it is not all unprecedented. Since JAXA records began in 1979, there have been a total of 10 century increases in the freezing season after 13th February (ordered by date):

13th February 2019: +104'786 km2 (yesterday)
14th February 2017: +110'137 km2
15th February 2017: +127'281 km2
15th February 2005: +114'256 km2
19th February 2014: +111'171 km2
20th February 2014: +110'795 km2
24th February 2013: +117'014 km2
24th February 2016: +149'990 km2
1st March 2012: +186'143 km2 (biggest increase)
12th March 2014: +115'282 km2 (latest century increase)

Worthy to mention here is that those late century increases are a phenomenon that really only started to occur regularly in the last 10 years.

25
Arctic sea ice / Re: The 2018/2019 freezing season
« on: February 06, 2019, 11:35:28 AM »
I think the Pacific sector may see some further decline / slow gain in the coming week.

There is a hurricane-force cyclone off the coast of the Kamchatka Peninsula (https://twitter.com/ZLabe/status/1092868696102494208). According to ECMWF it will maintain a lot of its power through the weekend and wander further north-east towards the Bering straight. There's a good possibility that this cyclone with the resulting waves up to 10m bring some disruption to sea ice in the Bering and Okhotsk Sea (attachment 1 is the forecast for Saturday).

Also temperature anomalies are being forcasted to stay a lot above normal over Bering, Chuckhi and Beaufort area in the coming week (attachment 2).

26
I always understood the total Greenland (or generally any) ice sheet mass change in a year to mainly be a result of the amount snowfall, melt and calving:
mass change = gain from snowfall - loss from melt - loss through calving
Is this correct?

https://climate.nasa.gov/vital-signs/ice-sheets/

The linked page contains a graph that has data until June 2017 and shows an ongoing downward trend in the Greenland total ice sheet mass.

Yes, the mass loss accelerated from 2003 up until 2012.  However, since then it has decelerated dramatically, to the point where it may actually be gained mass.

http://sciencenordic.com/how-greenland-ice-sheet-fared-2018

https://nsidc.org/greenland-today/

"Exceptional winter snow accumulation and heavy, summer snowfall, drove the net snow input mass to 130 billion tons above the 1981 to 2010 average. This was followed by a near-average melt and runoff period, resulting in a large net mass gain for the ice sheet in 2018 of 150 billion tons. This is the largest net gain from snowfall since 1996, and the highest snowfall since 1972. However, several major glaciers now flow significantly faster than in these earlier years. The net change in mass of the ice sheet overall, including this higher discharge of ice directly into the ocean, is not clear at this point but may be a smaller loss or even a small gain. This is similar to our assessment for 2017, and in sharp contrast to the conditions for the preceding decade."

Do I understand this analysis correctly that this downward trend could have been broken in 2017 and 2018? That would be great news.

27
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: January 03, 2019, 12:22:24 PM »
To conclude I'd like to take a look at the 365-day trailing average of Arctic sea ice extent.

The average extent of 2018 was 9'919'855 km2, this is:
- 2nd lowest on record
- 203'876 km2 higher than the record year 2016
- 35'785 km2 lower than the 3rd-placed-year 2017
*- All years except 2012/2016/2017/2018 stand above 10'000'000 km2.


The first graph shows the 365-day trailing average in the last 5 years. While there is some fluctuation in the past 2-3 years, the linear trend shows a clear decline. The lowest 365-day-average of Arctic sea ice extent was 30th March 2017 with 9'683'735 km2.

The second graph shows the development of the 365-day-average in 2018. I think the timeframe is too small for it to have any significance, but the trend slightly downward as well.

28
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: January 03, 2019, 12:07:22 PM »
Now a straight-forward statistics showing how many records were broken or nearly broken in 2018.

This year had:
- 68 days of lowest Arctic sea ice extent.
- 203 days where Arctic sea ice extent was ranked in lowest 3.
- 269 days where Arctic sea ice extent was ranked in lowest 5.

Out of the 68 records:
- 25 were in Juanuary
- 25 in February
- 7 in March
- 9 in April
- 2 in October

29
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: January 03, 2019, 12:02:19 PM »
Now onto some statistics regarding the day rankings in 2018. I'm really not sure if those have any significance, but I think they are interesting to look at nontheless.

The first "table" shows the average rank a day holds in that year. Read it as "A day in 2015 is ranked as 6.2 lowest in average".

2018 stands at 4.1, which is higher than the two previous years, but lower than all other years. So 2018 fits the trend of overall decline really well.


The second "table" shows the average rank a day held that year at the end of that year. Read it as "At the end of 2015, a day in 2015 was ranked as 3.8 lowest in average".

My interpretation of this statistics is that it should show whether the speed of ice decline is slowing or accelerating. 2018 is slightly above average, but this is mainly caused by the very high extent numbers in July, so I don't know it that tells us anything about the overall trend.

30
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: January 03, 2019, 11:40:29 AM »
December 2018 had an average Arctic Sea Ice Extent of 11'378'371 km2. This is:

 - 4th lowest on record
 - 85'479 km2 less than the 2010's (2010-2018) average
 - 96'038 km2 more than 2017
 - 377'435 km2 more than the record year 2016

The second image shows the ranks of average extent per month in the last 15 years. Read it as "March 2018 had the second lowest average Arctic sea ice extent in recorded history".

As you can see, there is a clear trend here of average extent declining, moreso in winter than in summer months in recent years.

31
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: January 03, 2019, 11:31:52 AM »
Back from holidays as well. Happy new year everyone from Switzerland.

I'll do some posts about things I observed this past month / year. Since this is my first year of following the cryosphere this closely and most people in this forum know a lot more than me, I'll try to focus on data and do as little interpretation as possible.

To start off, ASI Extent has passed the 12M km2 mark on 30th December. This is the second latest date of this happening with the latest being 2017 (2018) on 2nd January.

The timeframe around the minimum of 2018 (15.3.2018 - 15.3.2019) had 234 days of Arctic Sea Ice Extent below 12'000'000 km2, which is:

 - 2nd highest on record
 - 8 days more than the 2010's (2010-2018) average
 - 4 days more than 2017
 - 3 days less than the record year 2016

A lot of statistics covering Arctic sea ice extent show a slowing (some say even a halting) of decline since 2012. The "days below 12M km2 extent" shows the exact opposite. Maybe a sign of continued winter ice loss or maybe just a 4-year-long fluctuation, we will know more in the future. But at the moment it seems like the days of high extent numbers are getting fewer and fewer each year.

32
Science / Re: ICESAT-2
« on: December 13, 2018, 12:31:13 PM »
ICESat-2 seems to be off to a good start. NASA released this article 2 days ago.

https://www.nasa.gov/feature/goddard/2018/icesat-2-reveals-profile-of-ice-sheets-sea-ice-forests

Here is the section of the article that I find most interesting.

Quote
The first months of ICESat-2 data collected over Arctic and Antarctic sea ice reveal thin ice, thick ice, and features such as ice ridges. Areas of open water in the cracks between the ice floes, called leads, stand out in the data because of the difference in reflectivity between ice and water. By comparing the height of that water surface in the leads with the height of the ice, scientists are estimating ice freeboard and thickness. With the high precision of ICESat-2, plus the satellite’s six beams taking data simultaneously, researchers will have an unprecedented understanding of the thickness of sea ice, which will be used to help improve climate modeling and forecasts.


Plus, the ability to identify newly formed, thin ice will help researchers track the seasonal changes in remote polar regions, and understand the processes that drive those processes. The ice-thickness data will also help scientists improve computer models of how sea ice responds to Arctic warming, as well as forecasts of sea ice cover.


“We’ll have much higher resolution of where it’s ice and where it’s water in the marginal ice zones, where the compact ice cover meets the ocean, during melt and freeze-up,” Kwok said. “That’s going to be new science to think about.

And also:

Quote
Mission managers expect to release the data to the public in early 2019.

33
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: December 11, 2018, 08:55:06 AM »
2018 had 195 days of Arctic Sea Ice Extent below 11'000'000 km2, which is:

 - 2nd lowest highest on record
 - 6 days more than the 2010's (2010-2018) average
 - 6 days more than 2017
 - 13 days less than the record year 2016

34
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: December 05, 2018, 05:08:58 PM »
There was a discussion last year about how there are waves of above/below average melt/gain, and I think that has always been so, and probably due to temporary changes in wind, waves and temperatures. But the weather people hypothesise that global warming has weakened the polar jet stream and with big fat lazy Rossby waves weather patterns can stick around a lot longer.

I remember someone writing about "sticky weather" ? Perhaps this is showing up in longer waves of above/below average freeze/melt?

I have a very similar feeling regarding those "waves" that are getting slower and more extreme in intensity. Here are two tables from the last one and a half months.

The first table shows a new record ice gain from late October to late November. Then, starting from the date the first table ends, a new low record ice gain to today.

I am aware that these dates are cherry-picked, but it's still a rather remarkable development in my opinion. Not to forget that there was also the (probably record) slow start of the freezing season. A clear slow-fast-slow pattern so far this freezing season.

35
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: November 21, 2018, 04:04:44 PM »
Another interesting statistic to show the uniqueness of the current refreeze. The table shows the extent changes (JAXA) in the last 30 days (Oct 21 - Nov 20). 2018 is leading with a margin of over 400'000 km2 and the extent gain was over 1'000'000km2 higher than the 2010's average!

Another note I'd like to make is that the table considers all years from 1979-2018. Out of the years in the top 10, there are 4 from the 2010's, 4 from the 2000's and only 2 from before 2000. This shows that there are times of the year where the refreeze is actually going up, rather than down like the overall extent trend.

My theory, and please correct me if I'm wrong, is that this is the effect of the increased summer melt in the central seas. Especially the CAB, Laptev and Kara lose way more ice in summer than they did 20 years ago. But because of their northern and central location, they still refreeze 100% in winter anyway. But this (usually quite fast) freeze of those seas was around early October 20 years ago, it's now happening in late October and November. Therefore the upwards trend in October - November sea ice gain.

36
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: November 21, 2018, 09:11:10 AM »
To put current events a bit in perspective: The last time the daily JAXA arctic sea ice extent did not rank in the top 11 was 25th April 2012. Since then, every single day was in the lowest 11 at the time - until yesterday.

That's a great signal for the ice. But on the other hand, we all know what happened the months after the last time it was this "high" in 2012.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: November 20, 2018, 09:05:26 AM »
2008 is at 10'240'135km2, ranked 17th.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: November 15, 2018, 11:40:34 AM »
Not sure what to make of this all, but the ice gain over the past month is the second highest in the satellite history, with the gain over the past two weeks being the highest.  Based on current and forecast temperatures I expect this to continue in the short term.

Klondike Kat's statement in numbers:

2018 had the 2nd highest extent gain from November 1st to November 14th in satellite history. That's an impressive recovery from the very slow start of this year's freezing season.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: November 01, 2018, 09:40:57 AM »
October 2018 is over. Here are the numbers of the JAXA average extent of this month. 2018 is back down to rank 3 (after rank 5 in June, rank 9 in July and rank 6 in August and September) with an October average extent of 5'916'648 km2.


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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 29, 2018, 01:01:56 PM »
Having passed the 7M mark for this year, here's the table with the amount of days each year had with an extent below 7M.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 24, 2018, 02:11:06 PM »
In the table it's the average of the number of days of each year's extent below 6M.

But after reading your question, I figured it probably makes more sense to take the number of days the 2010's average extent was below 6M in the future. This number would be 68, equal to 2017.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 24, 2018, 01:02:39 PM »
Since we are past the 6'000'000 km2 mark for this year, here's a table showing the amount of days in which a year had an arctic sea ice extent <6'000'000 km2. 2018 placed 4th with 74 days. The leaders in this statistics are 2007 and 2012 with 77 days.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 17, 2018, 09:12:54 AM »
Thanks Juan and gerontocrat for your daily updates. They are highly appreciated by a lot of people. But as others have said already, only do them if you want to.

Already missing Juan's daily table, I tried to recreate it, I hope that is okay.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 15, 2018, 01:41:02 PM »
I am not referring to end-Oct but to this post by gregcharles and the follow-up by Phil.

Quote
lowest NIPR extent records for October 16 to 19 belong to 2007, the only remaining year before 2010 to have any of its days be the lowest extent. 2018 has a decent chance of ending that though.

2007's remaining records are most certainly safe for another year, except for maybe 1 day at most. Still, it is not unlikely that 2018 will set some new extent lows towards the end of the month.

Here is the extent-changes-needed-for-new-records-table from today. I've added a column displaying the average extent changes in the given timeframe to put the extent needed number a bit better in perspective. This shows that average extent increases from now on would lead to new records starting 22nd October.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 09, 2018, 01:46:55 PM »
So, here's an interesting tidbit: the current lowest NIPR extent records for October 16 to 19 belong to 2007, the only remaining year before 2010 to have any of its days be the lowest extent. 2018 has a decent chance of ending that though.

This one got me thinking how likely it is for 2018 to set new records in the near future and I came up with this small table. It shows, what average daily extent changes are needed to set a new record in x days.

How to read it (10 days as example): If 2018 has an average daily extent change of +96'125 km2 or less during the next 10 days, it will break the current record of 5'991'377 km2 held by 2007 for 19th October. I hope that kind of makes sense.

So, even with daily increases of 100k as of today, 2018 would still set a new record in 11 days.

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Quote from: NASA ICE, 21.09.2018
Week 1 update: #ICESat2 is looking great!
Solar array deployed, all subsystems turned on, and we’re busy checking everything out. Navigation works perfectly, guiding us along our planned orbit.
 ~1 week until it's time to open the door & turn on the laser!

Everything is looking good for our new hope for better data collection up there. We will probably get another update after the first laser tests. I'm really excited for this one.

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Arctic sea ice / Re: The 2018 melting season
« on: September 19, 2018, 02:23:51 PM »
As the freezing season thread has opened and the 2018 melting season comes (has come?) to an end, I'd like to throw a big THANK YOU at everyone who has contributed to this thread and the interesting discussions.

I am mostly a lurker on this forum but come here almost daily reading through the posts. This was the first melting season I followed like this and I have really learned a lot because of everyone here.

Looking forward to the freezing season now

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Arctic sea ice / Re: The 2018 melting season
« on: September 11, 2018, 09:27:44 AM »
Looks like the southern part of the ESS arm and the "Beaufort Island" are slowly melting away after all. On the other hand I think a small extent increase towards the Amundsen Gulf is observable.

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Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 07, 2018, 10:25:40 PM »
2018 is the 11th year with a minimum below 5'000'000 km². Since 2007, every year with exception of 2009 had a minimum below 5'000'000 km².

Here are the dates when the other 10 years passed the 5 million mark again in the freezing season, ordered from earliest to latest.

2014 - 21. September
2013 - 22. September
2010 - 25. September
2016 - 27. September
2017 - 29. September
2008 & 2015 - 30. September
2011 - 2. October
2007 - 9. October
2012 - 14. October

Let's see which position 2018 will take in this statistic

50
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: April 18, 2018, 11:26:05 AM »
Since we hit the 13 million km2 extent mark now, I decided to look at the dates when the extent hit this mark in previous years. I ordered them by the date it hit the mark and added the decade averages.

ASI Extent first time below 13 million km2 by year (JAXA):
2018: April 17
2016: April 19
2017: April 21
2004: April 22
2007: April 24
2006, 2014, 2015: April 26
2010's Average: April 28
2000's Average: May 4
1990's Average: May 13
1980's Average: May 21

edit: Looks like gerontocrat was faster than me, I'll leave the post up anyway.

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