Support the Arctic Sea Ice Forum and Blog

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - El Cid

Pages: [1] 2 3 ... 10
Arctic sea ice / Re: The 2021 melting season
« on: April 17, 2021, 10:02:17 AM »
April 11-16.


Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: March 25, 2021, 06:03:29 AM »
      Good point.  I would have more faith in latitudinal delay if the final ice was centered around the North Pole.  The current HYCOM thickness model shows bulk of the thick ice being well south of 80N in Beaufort and along ESS shore.  PIOMAS thickness is less southerly but somewhat similar to HYCOM, and even CS2SMOS which shows thick ice overall at higher latitude still does not have it centered around 90N.
      Apologies to whomever I copied the attached graph from that shows the expected location of the final 1M km2 ASI Extent.  Current distribution may be a one-year exception, but in March 2021 the thick ice is centered well south of where the final 1M km2 of ice graph says it should be centered.
     While true that higher melt rate in southern locations has affected the Vol., Ext. etc. ice loss trends, in terms of Sept. minimum we are already in the era when almost all the ice remaining ice at end of melt season is in the CAB.  Gerontocrat's "River Valley" Area graphs for individual seas,3426.msg303130.html#msg303130  shows that Barents, Greenland, Hudson Bay have been melting out for quite a while.  And that except for the Beaufort Sea and the CAB, the other high Arctic seas (ESS, Laptev, Kara) are already reaching or nearly reaching zero Area late in the melting season.
     Other Gerontocrat Volume graphs make the same point for Chukchi, CAA, and show even the Beaufort getting near zero.  That leaves the CAB as the last wall, and its late-season Volume is also less than what it used to be. 
     If getting down to the CAB as the final stand is going to slow down the trends, that should become apparent in a slowing of the trend lines over the next few years because we are already into the 'CAB last stand' era.  The later the Volume trend starts to slow the harder it has to bend away from zero.  The current straight-line trend has it reaching zero in 2033.

Arctic sea ice / Re: The 2020/2021 freezing season
« on: March 12, 2021, 11:41:56 PM »
A comparison GIF of the ice on March 9 2020 and 2021.

An alternative comparison.

Click to enlarge/animate
    Both the CS2SMOS, and especially the HYCOM, models indicate that the centroid of ice thickness will be at a lower latitude heading into 2021 melt season than it was in 2020. 

    The relative solar radiation by latitude chart (originally from Tealight) suggests that a 10 deg. lower latitude shift from 80 to 70 would extend the length of melting season above a 7 watt/m2 threshold by about two weeks for both the start and end date.  Thus a total of 4 weeks.  But the shift is less than 10 degs., and losing the highest lat. degrees has less effect than lower ones, i.e. going from 80 to 75N has less impact than going from 75 to 70N. 

     If the center of the ice is 5 deg. farther to the south, that might represent an earlier shift for the start of melting season by about 4-5 days and delay the end date by 4-5 days, thus increasing melt season duration by about 8-10 days.  Adding a few days at the start and end when there is just barely enough solar energy to cause melt probably doesn't mean much.  But being at a lower latitude also means that solar radiation is more intense throughout melt season, so a 5 degs. southerly shift would be significant.

     This is just speculation piled on top of speculation, but to the extent to which any of this is valid, it suggests that while the 2020-2021 freezing season left the ASI in decent condition in terms of the metrics, when you factor in the positioning of the ice, things may be more precarious for the coming melt season than the Volume and Extent numbers by themselves indicate.


North America
The images from Environment Canada show that Snow Cover Extent (SCE) is concerned, the snowmelt season is well underway, at least at lower latitudes. It may be that in North America the Snow Water Equivalent (SWE i.e. mass) is now also in decline.

SWE is still increasing strongly. The maximum on the y-axis on the graph was increased.
SCE dithering.

click images to enlarge

Arctic sea ice / Re: The 2020/2021 freezing season
« on: March 09, 2021, 07:35:32 AM »
September 8 - March 8.

The contrast between falling Snow Cover Extent (SCE) and increasing Snow Water Equivalent (SWE) continues to grow.

Once again the question is whether that thicker snow at higher latitudes will slow down snow melt significantly.

North America

While the snow at lower latitudes from the big storm has melted (i.e. mostly in the lower 48) , snow water equivalent has not gone down. That means more snow at high latitudes , i.e. mostly Canada, and average depth also increased.

Gradual reduction in snow cover extent and no reduction in snow water equivalent.

Click to enlarge attached images

Consequences / Re: COVID-19
« on: February 25, 2021, 04:22:07 AM »
Finally, a peer reviewed study about the Pfizer vaccine effectiveness in Israel, published in the NEJM. Seems like a well designed study confirming the randomized trial results in a real-life setting. A good read.



As mass vaccination campaigns against coronavirus disease 2019 (Covid-19) commence worldwide, vaccine effectiveness needs to be assessed for a range of outcomes across diverse populations in a noncontrolled setting. In this study, data from Israel’s largest health care organization were used to evaluate the effectiveness of the BNT162b2 mRNA vaccine.

All persons who were newly vaccinated during the period from December 20, 2020, to February 1, 2021, were matched to unvaccinated controls in a 1:1 ratio according to demographic and clinical characteristics. Study outcomes included documented infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), symptomatic Covid-19, Covid-19–related hospitalization, severe illness, and death. We estimated vaccine effectiveness for each outcome as one minus the risk ratio, using the Kaplan–Meier estimator.

Each study group included 596,618 persons. Estimated vaccine effectiveness for the study outcomes at days 14 through 20 after the first dose and at 7 or more days after the second dose was as follows: for documented infection, 46% (95% confidence interval [CI], 40 to 51) and 92% (95% CI, 88 to 95); for symptomatic Covid-19, 57% (95% CI, 50 to 63) and 94% (95% CI, 87 to 98); for hospitalization, 74% (95% CI, 56 to 86) and 87% (95% CI, 55 to 100); and for severe disease, 62% (95% CI, 39 to 80) and 92% (95% CI, 75 to 100), respectively. Estimated effectiveness in preventing death from Covid-19 was 72% (95% CI, 19 to 100) for days 14 through 20 after the first dose. Estimated effectiveness in specific subpopulations assessed for documented infection and symptomatic Covid-19 was consistent across age groups, with potentially slightly lower effectiveness in persons with multiple coexisting conditions.

This study in a nationwide mass vaccination setting suggests that the BNT162b2 mRNA vaccine is effective for a wide range of Covid-19–related outcomes, a finding consistent with that of the randomized trial.

Consequences / Re: COVID-19
« on: February 22, 2021, 02:56:10 PM »
First population based evidence of reduction by the first dose of both the Pfizer and AZ Oxford vaccines of severe disease requiring hospitalisation has been published today by Public Health Scotland:

There’s not a lot of data in the report but the results being reported for both vaccines would seem to be immensely encouraging:

“The Covid vaccination programme has been linked to a substantial reduction in hospital admissions, PA Media is reporting. The PA story goes on:

Researchers examined coronavirus hospital admissions in Scotland among people who have had their first jab and compared them with those who had not yet received a dose of the vaccine.

Scientists from the University of Edinburgh, the University of Strathclyde and Public Health Scotland examined data on people who had received either the Pfizer/BioNTech jab or the one developed by experts at the University of Oxford with AstraZeneca.

By the fourth week after receiving the initial dose, the Pfizer and Oxford/AstraZeneca vaccines were shown to reduce the risk of hospital admission from Covid-19 by up to 85% and 94%, respectively, they found.”

Fingers crossed this proves to be the case.

Consequences / Re: COVID-19
« on: February 21, 2021, 08:01:39 PM »
Mayo Clinic Study Suggests Efficacy of 1st Pfizer, Moderna Shot Increases With Time

The Minnesota-based clinic, in a study of 31,000 people in four US states who received at least one vaccine shot, found the inoculations were 75 percent effective 15 days after the first shot, and around 83% effective 36 days after the first shot; the figure climbs to 89% for people who received both doses

FDA-authorized COVID-19 vaccines are effective per real-world evidence synthesized across a multi-state health system

Consequences / Re: COVID-19
« on: February 18, 2021, 06:28:40 AM »
With a few more details, from the WSJ

New Israeli Study Suggests 95% Efficacy Rate With Pfizer Vaccine

A Covid-19 vaccination center in Israel on Feb. 4ODED BALILTY/ASSOCIATED PRESS
TEL AVIV—An Israeli study published Wednesday found a 95% efficacy rate against Covid-19 among 600,000 people one week after receiving two doses of Pfizer Inc. and BioNTech SE’s vaccine.

The study by Maccabi Healthcare Services, Israel’s second largest healthcare provider, found that just 608 out of 602,000 vaccinated people became infected with Covid-19. Of those who became infected in this group, only 21 were hospitalized, and of those, just seven developed serious symptoms.

Maccabi compared the vaccinated group with a control group of 528,000 people who weren't yet vaccinated or infected with Covid-19 and had similar demographic profiles. From this control group, 20,621, or 3.9%, became infected in the same period.

The results of the Maccabi study are similar to those of the original clinical study conducted by Pfizer, which found 95% efficacy against the virus. They are also similar to a study released Sunday by Israel’s largest healthcare provider, Clalit, which found a 94% drop in symptomatic Covid-19 infections among a vaccinated population.

“The findings show, without doubt, that the vaccine is the most effective way to eliminate the risk of COVID infection," said Dr. Anat Ekka-Zohar, the director of the division of data & digital health at Maccabi Healthcare Services.

Thanks to a steady supply of vaccines from Pfizer and an advanced digital healthcare system, Israel has vaccinated a higher percentage of citizens than any other country. Currently, 44% of all Israelis, or two-thirds of those eligible to be vaccinated, meaning those above 16 years old, have received their first shot, according to the Israeli health ministry.

Consequences / Re: COVID-19
« on: February 02, 2021, 03:51:48 AM »
Some good news:

Israel: We say with caution, the magic has started

Note blue lines, of 60+ years old (first to vaccinate), in the past 2 weeks:

~35% drop in cases
~30% drop in hospitalizations
~20% drop in critically ill

Stronger than in younger people & not seen in previous lockdown

These patterns were not observed in the previous lockdown, see same graphs for second lockdown

Yesterday we showed even bigger drops in cities vaccinated earlier:

Israel: Signs of vaccines affecting national pandemic dynamics

Drop in cases & hospitalizations of 60+ y/o in cities vaccinated early

Stronger than in late-vaccinated cities

Stronger than in younger people (only recently eligible)

Not seen in previous lockdown


Consequences / Re: COVID-19
« on: January 20, 2021, 04:07:13 AM »
Now we will have to turn our attention toward Israel. 27% of the population has been vaccinated and they keep pushing on, we should soon see a major dropoff in infection rates. I wonder what restrictions they still have and when they will exit those.

oren, what are the rules there now?
A (third) general lockdown begun a few weeks ago was extended until the end of January. Theoretically stores are closed except essential ones, services are closed, malls are closed, restaurants are closed except for home delivery, schools are closed, events are forbidden, meeting other people is forbidden with some few caveats, offices are closed except for essential employees. Compliance is much lower than the first lockdown in March, and the reality very different than what the rules say. Many stores have become essential or switched to online so in essence are open and you can walk in with a wink. Personal services (hairdresser etc.) can be had by illegal home visits. You can go anywhere with a good excuse and meet anyone. At most you might encounter a police checkpoint, all reported in traffic apps so can be avoided easily even where they exist. Some things are indeed closed like restaurant sit-down, malls and theaters. Schools are open in broad defiance for some sectors. Masks are generally worn but compliance is lower in some sectors, and actual masking is often sloppy. No wonder infection rates per capita are higher than even the UK and the US, but hopefully things will improve slowly as the lockdown continues.

The main issue is that the same population sectors which are responsible for most of the spread of the virus due to flaunting of social distancing rules are also those where vaccination rates are the lowest. These sectors are still holding crowded weddings if you can believe it, and keeping schools open despite state-dictated closure. (Yeah enforcement in Israel is poor and politically-driven).

Vaccination rate has slowed sharply from 100-150k per day to less than 50k per day mainly due to limitations of vaccine availability, but also by what seems to me like a slowdown in the uptake rate as the initial pool of people who want the vaccine got it. I get the feeling the total vaccination rate will taper off much earlier than 100%. Initially only people over 60 and were eligible, but a large number aged 50 and 40 got vaccinated anyway by standing in lines, sometimes for hours, hoping for leftovers which are quite common given the difficult logistical limitations of the Pfizer vaccine. In addition some special sectors such as military personnel and teachers and of course medical personnel got vaccinated regardless of age.

Number of hospitalized persons in serious condition is hovering at very high levels but has not grown in the last three days, and the 7-days average of new infections has finally hit a plateau.
It is still unknown how much the vaccines slow infections, but considering the antibody studies I can't believe it will not be a major effect. So in February we *should* see a much improved situation on both infections and hospitalizations.

Consequences / Re: COVID-19
« on: January 20, 2021, 01:10:10 AM »
Israel's Virus Czar: First Dose Of Vaccine Less Effective Than Pfizer Data Shows

The first dose of the Pfizer vaccine offers less protection against COVID-19 than US pharmaceutical giant Pfizer originally claimed, Israel's coronavirus czar told Hebrew media on Tuesday. 

"Many people have been infected between the first and second injections of the vaccine," Nachman Ash told Army Radio, adding that the first dose is "less effective than we thought" and "lower than [the data] presented by Pfizer."

Pfizer itself says a single dose of its vaccine is about 52% effective.

By contrast, those who had received their second dose of the Pfizer vaccine had a six- to 12-fold increase in antibodies, according to data released by Sheba Medical Center in Tel Hashomer on Monday.

Nachman Ash reportedly says it's not certain vaccines can protect against mutated coronavirus strains; 12,400 Israelis were infected with virus after receiving 1st shot; this figure includes 69 people who have received the second dose.

Over 2 million Israelis have had their first Pfizer shot. Over 400,000 have had the second.

Last week, Sharon Alroy-Preis, head of the Health Ministry’s public health department, announced that the vaccine curbs infections by some 50 percent 14 days after the first of the two shots is administered. She said that the data was preliminary, and based on the results of coronavirus tests among both those who have received the vaccine and those who haven’t, who are are serving as a de facto control group.

At the same time, however, other, somewhat contrary data was released by Israeli health maintenance organizations: According to figures released by Clalit, Israel’s largest health provider, the chance of a person being infected with the coronavirus dropped by 33% 14 days after they were vaccinated; separate figures recorded by the Maccabi health provider showed the vaccine caused a 60% drop in the chances for infection after taking the first shot.

... Amid warnings that 30% to 40% of the new infections were being driven by a Covid-19 variant first identified in the UK, the Israeli cabinet was meeting on Tuesday to consider tightening existing restrictions. Some analysts, however, have put the prevalence of the new variant at lower levels.

The cabinet had been warned by Ash that the new variant was set to become the main source of infections in Israel within weeks.

Consequences / Re: COVID-19
« on: January 20, 2021, 12:57:02 AM »
This article is a preprint and has not been certified by peer review:

SARS-CoV-2 reinfection in a cohort of 43,000 antibody-positive individuals followed for up to 35 weeks

Background Reinfection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been documented, raising public health concerns. Risk and incidence rate of SARS-CoV-2 reinfection were assessed in a large cohort of antibody-positive persons in Qatar.

Methods All SARS-CoV-2 antibody-positive persons with a PCR-positive swab ≥14 days after the first-positive antibody test were individually investigated for evidence of reinfection. Viral genome sequencing was conducted for paired viral specimens to confirm reinfection.

Results Among 43,044 anti-SARS-CoV-2 positive persons who were followed for a median of 16.3 weeks (range: 0-34.6), 314 individuals (0.7%) had at least one PCR positive swab ≥14 days after the first-positive antibody test. Of these individuals, 129 (41.1%) had supporting epidemiological evidence for reinfection. Reinfection was next investigated using viral genome sequencing. Applying the viral-genome-sequencing confirmation rate, the risk of reinfection was estimated at 0.10% (95% CI: 0.08-0.11%). The incidence rate of reinfection was estimated at 0.66 per 10,000 person-weeks (95% CI: 0.56-0.78). Incidence rate of reinfection versus month of follow-up did not show any evidence of waning of immunity for over seven months of follow-up. Efficacy of natural infection against reinfection was estimated at >90%. Reinfections were less severe than primary infections. Only one reinfection was severe, two were moderate, and none were critical or fatal. Most reinfections (66.7%) were diagnosed incidentally through random or routine testing, or through contact tracing.

Conclusions Reinfection is rare. Natural infection appears to elicit strong protection against reinfection with an efficacy >90% for at least seven months.

But it doesn't matter (if true). All their brains have been fried anyway.

the Us and Europe still talk like they should be aplauded for getting to net zerro by 2050. we need a ban on new ff infrastructure ice vehicles today. net zero by 2030 or 2035 should be our goal.
It should, but it isn't. If net zero goal is placed within a decade, people currently in power would have to make the tough decisions. They don't want to do that.

As net zero goal is placed further into the future, it's all business as usual until the powers-that-be conveniently retire. Technology may reduce some emissions so everybody can pretend things are being done, when in fact nothing isn't.

Arctic sea ice / Re: The 2020/2021 freezing season
« on: January 13, 2021, 08:56:49 AM »
January 2-12.


Consequences / Re: COVID-19
« on: January 07, 2021, 11:18:28 PM »
At Least Eight US States Have Now Confirmed a Case of the UK Covid-19 Variant

Officials in Texas and Connecticut have announced that the UK variant of Covid-19 has been identified in their states.

The variant appears to spread more easily, although there's no evidence that it's any more deadly or causes more severe disease, according to the Centers for Disease Control and Prevention (CDC).

Harris County Public Health in Texas said in a statement Thursday the first patient was a male between 30 and 40 with no travel history, which implies the variant has been transmitted locally.

... Later, Connecticut Governor Ned Lamont said health officials in his state had identified two cases of the variant, which would bring the count for the US to at least 56 cases. [... 5 miles down the road ...]

“The two individuals are between the ages of 15 and 25 and both reside in New Haven County. Both individuals recently traveled outside Connecticut – one to Ireland and the other to New York State – and both developed symptoms within 3 to 4 days of their return,” Lamont’s office said in a statement.

“Genetic sequencing of the virus has confirmed that the two cases are unrelated. The individuals’ specimens were collected earlier this month and subsequently tested positive.”

... At least eight states have now confirmed a case of the variant. The others are California, Florida, Colorado, Georgia, New York and Pennsylvania.


Pennsylvania Reports First Confirmed Case of COVID-19 Variant

HARRISBURG, Pa. - The new COVID-19 variant first discovered in the UK has made its way to Pennsylvania.

Someone in Dauphin County, which is near Harrisburg, tested positive for the variant, the first confirmed case in Pennsylvania, said the state Department of Health in a news release Thursday.

The person had known international exposure, and suffered mild symptoms, but has since recovered, officials said. Contact tracers have reached out to anyone who was in close contact with the person.


Los Angeles Is Reporting One Covid Death Every Eight Minutes

... Cases have increased 941% since November 1 and so far, the rate of new cases in January is double what it was in December, according to Ferrer. In the past two months, the positivity rate in LA County has jumped from 3.8% to 21.8%.

Hospitalizations are 10 times higher than they were on November 1, and Health Services Director Christina Ghaly warns that yet another surge is expected within the next two weeks. More than 8,000 people are currently hospitalized, with 20% in intensive care units and 19% on ventilators.


Patients In Intensive Care In the UK to Receive Arthritis Drugs as Trial Shows Reduction In Mortality

Results from the government-funded clinical trial — published online on Thursday, but not yet peer-reviewed — showed the drugs, Tocilizumab and Sarilumab, reduced the relative risk of death by 24%, when either were administered to patients within 24 hours of entering intensive care, the Department of Health said in a press release. They also reduced time in hospital by an average of seven to 10 days.

The government will update its guidance on Friday to encourage the use of these drugs for Covid-19 patients in intensive care. The drugs are typically available in UK hospitals.

During the trial, the drugs were administered in addition to a corticosteroid, such as dexamethasone, which is already provided in the standard of care, the press release said. 

Patients receiving the current standard of care alone experienced a mortality rate of 35.8%. This was reduced to 27.3% using tocilizumab or sarilumab, a 24% relative reduction in risk of mortality.


London "May Run Out of [Hospital] Beds" In Next Few Days, Mayor Says

London “may run out of [hospital] beds” in the “next few days” due to the surge in Covid-19 cases in the capital, London Mayor Sadiq Khan said on Thursday.

... Khan, when asked by LBC Radio if Covid-19 was “out of control” in London, said: “Yes. This virus is out of control."
He added: "The NHS is on the cusp of being overwhelmed. There has been no time during this pandemic where I’ve been more concerned than I am today.”
Khan implored Londoners to “stay home” and said National Health Service (NHS) workers “are stretched, they are overworked, many of them are suffering trauma that may take years to recover from.”


English City Set to Run Out of Pfizer/BioNTech Vaccine Doses By Friday

The English city of Birmingham will run out of Pfizer/BioNTech vaccine doses on Friday with "no clarity on when further supplies will arrive," local officials warned on Thursday in a letter sent to UK Health Secretary Matt Hancock.

... Birmingham "has not yet been supplied with any AstraZeneca [vaccine] stock." ...  "In addition, it remains unclear who is responsible for overseeing the vaccination programme in Birmingham and whom we should hold to account for progress and delivery," the letter reads.


Infection Rates Were Sharply Higher In Counties Where Universities Held Classes In Person.

Incidence rates in those counties rose more than 50 percent in the first three weeks after classes started, compared with the previous three-week period, according to a new study by the Centers for Disease Control and Prevention. By contrast, infection rates declined in counties without large universities or where large universities held classes remotely last fall, the study said.

... Infection rates went on falling — by an average of 18 percent — where large universities chose to teach remotely, the researchers found, but the rates shot up where in-person instruction was underway.

The findings come as many students who were home for the holidays prepare to return to campus. They will converge on college towns at a time when the virus is surging in many parts of the country, overwhelming hospitals and straining health care services.


As Americans were transfixed by the spectacle of the Capitol under siege, the coronavirus continued to sweep across the United States.

Officials reported at least 3,964 new coronavirus deaths in the United States on Wednesday, a new single-day record.

... “Most Americans don’t want to know, don’t want to acknowledge, don’t really want to recognize, and certainly — even as it’s descending upon us — do not appear to understand the dire circumstances that we are facing,” said Dr. Marjorie Bessel, the chief clinical officer at Banner Health, a major hospital network in Arizona.

With an average of 118.3 new cases per 100,000 people, Arizona has become what health officials call the latest “hotspot of the world” because of soaring case loads.

Arizona Gov. Doug Ducey has declined to institute a statewide mask mandate even as the state reports the highest rate of new cases in the US

... And with no good system in place to identify genetic variations of the virus, experts warn, the government will be hard pressed to track the UK & SA variants, leaving health officials in the dark.


JERUSALEM — Israel faces a tightened lockdown this week as officials fear that the more transmissible British variant of the virus is spreading rapidly and its vaccine supplies are running low.

“We are at the height of a global pandemic that is spreading at record speed with the British mutation,” Prime Minister Benjamin Netanyahu said in a video statement late Tuesday, justifying the government’s decision to impose a full national lockdown that will shutter most schools and all nonessential workplaces for at least two weeks.

“Every hour we delay, the quicker the virus is spreading, and it will exact a very heavy price,” he added.


Australian State Enters Lockdown After UK Strain Detected

Australia’s Queensland state enforced a three-day lockdown in Brisbane, the state capital, from Friday evening after a hotel quarantine worker tested positive for the more contagious variant of Covid-19 that emerged in Britain last month.

This is the science article Rogelj is referring too:

Is there warming in the pipeline? A multi-model analysis of the Zero Emissions Commitment from CO2


Thanks for posting the link to the science study.  I apologize for not including it in my original post.

Here's the abstract and some supporting excerpts:

MacDougall, A. H., Frölicher, T. L., Jones, C. D., Rogelj, J., Matthews, H. D., Zickfeld, K., Arora, V. K., Barrett, N. J., Brovkin, V., Burger, F. A., Eby, M., Eliseev, A. V., Hajima, T., Holden, P. B., Jeltsch-Thömmes, A., Koven, C., Mengis, N., Menviel, L., Michou, M., Mokhov, I. I., Oka, A., Schwinger, J., Séférian, R., Shaffer, G., Sokolov, A., Tachiiri, K., Tjiputra , J., Wiltshire, A., and Ziehn, T.: Is there warming in the pipeline? A multi-model analysis of the Zero Emissions Commitment from CO2, Biogeosciences, 17, 2987–3016,, 2020.

Back to top

The Zero Emissions Commitment (ZEC) is the change in global mean temperature expected to occur following the cessation of net CO2 emissions and as such is a critical parameter for calculating the remaining carbon budget. The Zero Emissions Commitment Model Intercomparison Project (ZECMIP) was established to gain a better understanding of the potential magnitude and sign of ZEC, in addition to the processes that underlie this metric. A total of 18 Earth system models of both full and intermediate complexity participated in ZECMIP. All models conducted an experiment where atmospheric CO2 concentration increases exponentially until 1000 PgC has been emitted. Thereafter emissions are set to zero and models are configured to allow free evolution of atmospheric CO2 concentration. Many models conducted additional second-priority simulations with different cumulative emission totals and an alternative idealized emissions pathway with a gradual transition to zero emissions. The inter-model range of ZEC 50 years after emissions cease for the 1000 PgC experiment is −0.36 to 0.29 ∘C, with a model ensemble mean of −0.07 ∘C, median of −0.05 ∘C, and standard deviation of 0.19 ∘C. Models exhibit a wide variety of behaviours after emissions cease, with some models continuing to warm for decades to millennia and others cooling substantially. Analysis shows that both the carbon uptake by the ocean and the terrestrial biosphere are important for counteracting the warming effect from the reduction in ocean heat uptake in the decades after emissions cease. This warming effect is difficult to constrain due to high uncertainty in the efficacy of ocean heat uptake. Overall, the most likely value of ZEC on multi-decadal timescales is close to zero, consistent with previous model experiments and simple theory.

The analysis here has shown that across models decadal-scale ZEC is poorly correlated to other metrics of climate warming, such as TCR and ECS, though relationships may exist within model frameworks (Fig. 12). However, the three factors that drive ZEC, ocean heat uptake, ocean carbon uptake, and net land carbon flux correlate relatively well to their states before emissions cease. Thus, it may be useful to conceptualize ZEC as a function of these three components each evolving in their own way in reaction to the cessation of emissions. Ocean heat uptake evolves due to changes in ocean dynamics (e.g. Frölicher et al., 2015) as well as the complex feedbacks that give rise to changes in ocean heat uptake efficacy (Winton et al., 2010). Ocean carbon uptake evolution is affected by ocean dynamics, changes to ocean biogeochemistry, and changes in atmosphere–ocean CO2 chemical disequilibrium, where the latter is also influenced by land carbon fluxes (e.g. Sarmiento and Gruber, 2006). The response of the land biosphere to cessation of emissions is expected to be complex with contributions from the response of photosynthesis to declining atmospheric CO2 concentration, a continuation of enhanced soil respiration (e.g. Jenkinson et al., 1991), and release of carbon from permafrost soils (Schuur et al., 2015), among other factors. Investigating the evolution of the three components in detail may be a valuable avenue of future analysis. Similarly, given their clearer relationships to the state of the Earth system before emissions cease, focusing on the three components independently may prove useful for building a framework to place emergent constraints on ZEC. Future work will explore evaluation opportunities by assessing relationships between these quantities in the idealized 1 % simulation and values at the end of the historical simulations up to present day.

Our analysis has suggested that the efficacy of ocean heat uptake is crucial for determining the temperature effect from ocean heat uptake following cessation of emissions. Efficacy itself is generated by spatial patterns in ocean heat uptake and shortwave cloud feedback processes (Rose et al., 2014; Andrews et al., 2015). Thus, evaluating how these processes and feedbacks evolve after emissions cease is crucial for better understanding ZEC. As the spatially resolved outputs for ZECMIP are now available (see Data availability at the end of the paper), evaluating such feedbacks presents a promising avenue for future research.

Here we have analysed model output from the 18 models that participated in ZECMIP. We have found that the inter-model range of ZEC 50 years after emissions cease for the A1 (1 % to 1000 PgC) experiment is −0.36 to 0.29 ∘C, with a model ensemble mean of −0.07 ∘C, median of −0.05 ∘C, and standard deviation of 0.19 ∘C. Models show a range of temperature evolution after emissions cease from continued warming for centuries to substantial cooling. All models agree that, following cessation of CO2 emissions, the atmospheric CO2 concentration will decline. Comparison between experiments with a sudden cessation of emissions and a gradual reduction in emissions show that long-term temperature change is independent of the pathway of emissions. However, in experiments with a gradual reduction in emissions, a mixture of TCRE and ZEC effects occur as the rate of emissions declines. As the rate of emission reduction in these idealized experiments is similar to that in stringent mitigation scenarios, a similar pattern may emerge if deep emission cuts commence.

Overall, the most likely value of ZEC on decadal timescales is assessed to be close to zero, consistent with prior work. However, substantial continued warming for decades or centuries following cessation of emissions is a feature of a minority of the assessed models and thus cannot be ruled out purely on the basis of models.

Arctic background / Re: Distribution of sea ice around Iceland from 1877
« on: December 09, 2020, 01:00:07 AM »
Trausti Jónsson, the notable Icelandic Meteorologist has a very interesting blog on Icelandic weather and climate.

He used to produce some blogs in english but most are in Icelandic.

Unfortunately some of the google translate efforts on the blog's icelandic is a complete mess. But here is the link.

His statistical charts are always easy to read. Here is also a summary of the weather conditions for 1881 :

The winter of 1880 to 1881 is the coldest known since the beginning of continuous measurements in this country. In Stykkishólmur, December 1880 is the coldest December known, February 1881 is the coldest of all February and March is by far the coldest of all March. January 1918 was colder than January 1881, but other months of the winter of 1917 to 1918 are not half as long as the same months of 1880 to 1881.

By the sea side of southwestern Iceland, the frosts were not quite as severe as elsewhere. In Reykjavík, for example, it seems to have been colder in February and March 1866 than in 1881, and there are more February months that were colder in Reykjavík than in 1881. The same can be said of the Westman Islands.

September was the only month of the year that can be considered warm, the temperature in October and November was just over the average of the years 1931 to 2010 and April, May and December just below. Other months are considered cold. In fact, in April and May, temperatures were slightly above the southwestern average, but below that in the northeastern part of the country. The highest temperature of the year was measured at Valþjófsstaður in Fljótsdalur, 21.5 degrees on 18 June and at a similar time at Bergstaðir in Svartárdalur in Húnavatnssýsla. The temperature also reached 20 degrees at Grímsstaðir á Fjöllum on the 3rd of September.

The highest frost of the year was measured in Siglufjörður on March 21, -36.2 degrees, the highest known in March in this country. On April 1, the frost was measured at the same place -30.2 degrees, the highest that has been measured in the country in April. Currently, there are certain doubts surrounding these Siglufjörður records - and it is also uncomfortable that no measurements were made in March 1881 at stations that have the most minimum temperature records in the country.

Consequences / Re: COVID-19
« on: November 21, 2020, 07:32:04 PM »
elsewhere ...


Steady Work: El Paso County Seeks Workers to Move 200-Plus Bodies at Morgue, Trailers

There is a gruesome sign of the times in El Paso, Texas.

El Paso County put out a call Thursday night for the immediate hiring of morgue attendants to help with the growing number of COVID-19 dead

...The morgue attendants are needed immediately and will work at the Medical Examiner’s Office. The County is seeking to hire enough staff to rotate assignments and shifts throughout the week and weekend as the County is bracing for an increase in COVID deaths.

Morgue attendants will be provided with maximum PPE, and will receive a COVID-19 test before starting. Morgue attendants are tasked with physically moving those who have died of complications related to COVID-19 infections. Applicants must be able to lift between 100 pounds to 400 lbs., with assistance. The position pay between $15 to $27 per hour.

On Thursday, the El Paso County Medical Examiner’s Office had 247 bodies at the morgue and inside nine refrigerated trailers serving as mobile morgues, El Paso County Judge Ricardo Samaniego said in news release. The number is growing by10-20 bodies each day.
Many hands; light work

In Oregon, mobile morgues are now in place along with new surge tents. In that state, they're setting daily records not just for COVID-19 cases but also for hospitalizations and deaths.


Troops with the Texas National Guard have been deployed to El Paso to help with the morgue crisis, according to the Texas Division of Emergency Management.

“After completing an assessment of the situation on the ground in El Paso County this week, the state has mobilized a team of 36 Texas National Guard personnel to provide mortuary affairs support beginning at 0900 tomorrow," said a spokesperson with TDEM.

..."As we've seen a rapid increase in cases and hospitalizations, we are unfortunately also seeing a spike in deaths. We have been working closely with funeral homes and mortuaries to assist with increased capacity and coordination of resources,” said Mayor Dee Margo. “The Texas Military will provide us with the critical personnel to carry out our fatality management plan and we are very grateful to them for their ongoing support."

The City of El Paso in partnership with the County of El Paso has secured a central morgue location to further support the Medical Examiner’s Office, funeral homes and mortuaries with additional capacity.

Arctic sea ice / Re: The 2020/2021 freezing season
« on: November 09, 2020, 11:00:31 AM »
I'll try to put my thoughts together in something more coherent, but let me put it this way, at the most elemental level:

It's all about Enthalpy.

Increased capture, reduced outgoing radiation mean the total heat present in the Arctic ocean has greatly increased.  (restricted by increased water vapor content in the atmosphere, along with additional CH4 and the increases in CO2... remember just how powerful a green house case H20 is...)

Ice can't form until sufficient heat has left the ocean surface to permit phase change to take place.  We already know that the water column has been disrupted, and that Atlantic water (and heat carried with it) is much closer to the surface and more accessible than the past.

Simply put, with the current energy balance, the Arctic can't dump the heat fast enough.

Even without the present throttling effects of weather (higher atmospheric temperatures and increased humidity, among other factors), the typical export of heat out of the atmosphere is not going to be able to dissipate the additional heat captured during the melt season. Heat simply won't get radiated out of the top of the atmosphere fast enough.

So, the bigger pile means there is that much more heat present which must get moved *somewhere* before the physics of phase change will permit the ice to form, over very large areas of the Arctic.

Unfortunately I don't have quantitative values to present here on this, but I think the qualitative argument should still be compelling.  As a rough estimate, the Arctic picked up something like 30% more energy this year during the melt season, *before* we factor in intrusion of Atlantic heat.

It can't get dumped fast enough.

Consequences / Re: COVID-19
« on: November 02, 2020, 01:51:56 PM »
Do we want a few thousand more deaths by January, or do we want a quarter million more? That's decided on November 3rd.
Transfer of power is in January. The election won't make a big difference until then.

all over the world the second wave is similar:
- mostly younger people get it, so mortality is way down
- there is also more testing capacity, so more cases are found than before
- and finally: it is still going up, and median mortality from infection is close to a month, so death numbers will still go way up

Chris Whitty showed interesting data (too much for the political journalists).
The heatmaps show clearly how the virus spreads from young adults to older age groups.

Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 21, 2020, 03:28:25 PM »
The ice on the Eurasian side of the N pole is slightly greater than 1 meter thick according to Russian reports. They just sent a new icebreaker to the pole to test its performance but the ice was too thin to test it. They hoped to find some 3 m thick ice but icebreaker went to the pole unhindered by any thick ice. From the Barents Observer

“Ice tests are still ahead, probably this year, because now ice tests did not work out, the ice thickness was 1,1 to 1,2 meters. It was thin and loose, the icebreaker received no resistance at all,” Shchapin says.

He adds: “We tried to find a three-meters ice floe, but they did not find it.”

Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 21, 2020, 11:57:41 AM »
NSIDC ease-grid ice sea age update. The nearest clear day I found on Worldview for comparison in the Beaufort was oct8.
click for animation.
edit: 2000-2020 animation here

Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 20, 2020, 08:37:15 AM »
October 15-19.


Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 17, 2020, 11:22:32 AM »
Yep, worst start to a freezing season we have ever seen. The maps at Climate reanalyzer are crazy.

The northern hemisphere temperature anomalies are huge for both the air and the oceans. In the southern hemisphere La Niña is cranking up with intense atmospheric convection over Indonesia, strong trade winds across the Pacific and intense upwelling along the coast of South America and along the equator in the eastern Pacific. There is now a large imbalance in the thermal anomalies and the Arctic is where the largest warm anomalies are found.

The heat content of the north Atlantic is at record high levels in the historic record, and according to proxies the past 2000 years or more. This is a set up for a winter with a weak polar vortex and strong intrusions of warm air from both the Atlantic and Pacific oceans - a poor freezing season. ON the other hand, there's a fair chance of w midwinter sudden stratospheric warming and strong high pressure over the pole which could enhance midwiinter freezing. There is hope that after a record poor start to the freezing season that January through March could be good for new ice. I think there's a better than average chance of a SSW this winter given the La Niña and westerly QBO.

Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 10, 2020, 07:38:25 AM »
October 5-9.


Arctic sea ice / Re: The 2020/2021 freezing season
« on: September 26, 2020, 07:00:00 AM »
September 21-25.


Consequences / Re: COVID-19
« on: September 26, 2020, 01:14:05 AM »
The Lancet: First nationally representative estimate of COVID-19 seroprevalence in the U.S. suggests few in the population developed antibodies in the first wave

Nation-wide cross-sectional analysis of U.S. patients receiving dialysis finds fewer than 10% of people had COVID-19 antibodies by July 2020, and fewer than 10% of those with antibodies had been diagnosed by antigen or PCR testing. *

Researchers say this representative population is ideal for studying the general spread of COVID-19 in the U.S. because these patients undergo monthly, routine blood draws and represent other similar COVID-19 risk factors such as age, non-white race, and poverty. * COVID-19 control efforts should prioritize minorities and people living in densely populated areas to prevent general community spread.

The first cross-sectional, nation-wide analysis of more than 28,000 patients on dialysis in the U.S. found that fewer than 10% of U.S. adults had COVID-19 antibodies as of July 2020 and fewer than 10% were diagnosed. Published today in The Lancet, the new study also shows higher COVID-19 infection rates among ethnic minorities and people living in lower-income, high density, urban areas - underling the need for COVID-19 public health efforts that prioritize these populations in order to prevent general community spread.

Researchers from Stanford University explain that patients on dialysis represent an important population to study general COVID-19 seroprevalence. These patients already undergo routine, monthly laboratory studies and represent similar risk factors to contracting COVID-19 as the general population, including age, non-white race, and poverty. Unlike community-based surveys, where a select group may show up for or agree to be tested and require a significant on-the-ground effort to launch, patients on dialysis are amenable to random sampling as part of their routine care.

The study follows previous findings from recent seroprevalence studies of highly affected countries and regions (e.g. Wuhan, China, and Spain), which have shown that despite the intense strain on resources and unprecedented excess mortality, rates of seroprevalence at the population level remain low. Other seroprevalence studies of the U.S. population have been restricted to regional hotspots, such as New York City.

... Findings showed that, compared to the majority non-Hispanic white population, people living in predominantly Black and Hispanic neighborhoods experienced a two- to four-times higher likelihood of COVID-19 infection (rates of COVID-19 infection were 11.3% to 16.3% in Black and Hispanic neighborhoods, compared to 4.8% in the majority non-Hispanic white population) while poorer areas experienced a two-times higher likelihood, and the most densely populated areas showed a 10-times higher likelihood of SARS-CoV-2 seropositivity.

In the study, researchers tested the seroprevalence of SARS-CoV-2 antibodies in a randomly selected representative sample of 28,503 patients to provide a nationwide estimate of exposure to SARS-CoV-2 during the first wave of the pandemic.  ... Accounting for the externally validated test sensitivity, seroprevalence ranged from 8.2% to 9.4% in the sampled population. Researchers estimated the SARS-CoV-2 standardized seroprevalence in the U.S. population to be approximately 9.3%. The authors also found significant regional variation from less than 5% in the western United States to greater than 25% in the northeast.

"This research clearly confirms that despite high rates of COVID-19 in the United States, the number of people with antibodies is still low and we haven't come close to achieving herd immunity. Until an effective vaccine is approved, we need to make sure our more vulnerable populations are reached with prevention measures," said study author Julie Parsonnet, MD, a Professor of Medicine at Stanford University.


A 'Climate Anomaly' Worsened World War I and the 1918 Flu Pandemic, New Research Suggests

Arctic sea ice / Re: The 2020 melting season
« on: September 16, 2020, 03:01:54 AM »
It's not just a SST thing in the Barents, Kara and Laptev seas. The heat goes town to 30m or more. Compare the 30 m Arctic temperatures of this year with 2019 on Mercator ocean and you will see that there's much more ocean heat on the Atlantic side this year than last. On the other hand, there's less heat on the Pacific side. Over both sides, there's much more heat this year, but there is almost always a see saw effect in the Arctic between the Atlantic and Pacific.

Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: September 14, 2020, 12:24:42 AM »
It wouldn't be much of a rebound anyways when you consider how thin all of the ice is.

What good is 4 year old ice that's under a meter thick
It’s more resilient than FYI under a meter.
<mass snippage>

Weather will be the determinant of the pack's survival, not the existing ice.

jdallen pretty convincing. I agree with almost everything you explain. Still that does not negate that, if we have that 7% of ice that has become older in the Western CAB post-2016, let’s count with its existence for future years. My belief is that it does matter, it is one of few negative feedbacks that the Arctic ice has to avoid imminent oblivion, that is: some regeneration of old ice if several years seasons do not push it away one direction or another.

I just happen to believe we are in for a gradual decline, which I know is not a popular opinion here. Yet some folks are noting that “this year would be creating big news if it wasn’t because of 2012”, yes, and that’s because of the current gradual decline of which 2012 was the exception.

I Used to believe 2030 was a good BOE prediction, but I am not so sure when one counts some negative feedbacks: extended falls after bad seasons lead to enormous late heat release, increased snowing, later springs, rebound years; years in a row with low or moderate CAB ice export lead to MYI rebound; warm ocean currents not easily reaching the western CAB ice...
mind you, I agree that a very bad year before 2030 might come and ice extent can go down even 1 m km2 but that would probably be exceptional, followed by rebounds, back to the gradual downhill track as it has happened post 2012, clearly.
Anyway, this is all speculation, reason why I post it here.
Thanks for shifting the discussion here.

I still think 2030-ish is the way to bet as far as a BoE is concerned, and agree that we'll get years if not decades of "dead cat bounces" while the Arctic as a system languishes in a marginal condition between the previous and next "stable" state.

I think my primary criticism about the value of MYI is more nuanced than may have come across in my OP.

There is no question that MYI was key to buffering and balancing the Arctic as a system, especially pre-2007.  The key function it served really didn't have to do with the implied latent energy uptake it represented.  MYI doesn't absorb more energy that FYI when melting.  The heat budget for phase change remains the same.  Rather, it was it's mechanical strength, across vast stretches of the pack which helped stabilize the system as a whole.

Part of that strength depended seriously the temperature of the ice as much as it did on its salt content - ice at -20c is almost as hard as bedrock - and has nearly the same mechanical strength.  So, pre-"modern" era conditions with millions of KM2 MYI and sub -10c temperatures meant that wind and other kinetic forces could be spread across very large areas with relatively little damage, and, that there would be little movement or disintegration of the ice outside of the pack margins.  This has made the system  more or less stable since the last of the Laurentide ice sheet vanished over 4500 years bce. (Prior to this, it was probably stronger.)

It's thickness ->at scale<- was important as well, as it meant year over year, it could lose 2+m of thickness, still remain in place, and provide a similarly broad-scale platform for re-deposition of new ice from below and new fresher ice refrozen from melt above.  It tended to stay in place.  It tended to keep albedo high, and by nature of strength and coverage, limit seasonal uptake of heat.  These last were as if not more important than the thermal inertia the ice itself provides.

Scroll forward now to the modern era, particularly at key junctures like 2007, 2010 (an underrated melt year), 2011 and 2012.  I'm adding a link to one of my favorite graphics by Jim Pettit here to help illustrate:

Those years mentioned are key in they are points in which the melt season destroyed large areas of MYI.  2010 in particular is notable for that, as even though extent and area did not drop to record levels, it was the first year we observed volume drop below 5,000 km3.  2007 was the first below - WAY below - approximately 9000km3 (2006 was 8993km3).  2011 and 2012 were years that continued the trend, dropping volume under 5000km3 and progressively chipping away at what some of used to call "matrix pack"; called such because of the very regular way it would fracture, essentially creating what could be considered fault lines in the ice while mostly retaining strength and coherence.

Those losses of volume and by extension MYI are critical to set the stage for what we see starting most dramatically in 2016.  The winter pack now fractures and recombines at much lower scales, eliminating the resistance it used to have to mechanical forces, and making the entire pack as a whole far more mobile.  Combine this with increasing advection of heat from southerly seas, and you have the new seasonal regime we now see. 

The result is, we have nothing like the larger expanses of MYI we used to see, which unbroken might cover 10's of thousands of km2. We are lucky if we see blocks of more than about 2500.  And because of warmer temperatures overall, for longer periods of both the melt and refreeze seasons, that relict ice has nothing like the mechanical strength of the old pack.

So, to finish my thought for the moment and conclude, MYI was far more important for the structure and mechanical characteristics it provided than it was for any sort of thermal component.  So while it exists now, it has nothing like the structure it had in the past, and because of that is only marginally less vulnerable than FYI when exposed to the conditions we now see during the melt season.  Without that structure, it doesn't really provide a buffer against loss as it used to.

Arctic sea ice / Re: The 2020 melting season
« on: September 04, 2020, 12:18:16 PM »
Todays daily images and animation.
(Larger gif on the twitter page)

Arctic sea ice / Re: The 2020 melting season
« on: September 03, 2020, 05:56:29 AM »
August 29 - September 2.


Consequences / Re: COVID-19
« on: September 03, 2020, 02:06:01 AM »
US Public Health Departments Being Told to Prepare November Vaccine Distribution

Health officials across the US have reportedly been notified that they should expect a coronavirus vaccine available to health workers and high-risk groups by November, amid concerns the accelerated vaccine development process has become politicized.

The Centers for Disease Control and Prevention (CDC) informed health officials that “limited Covid-19 vaccine doses may be available by early November 2020”, the New York Times reported.

Meanwhile, in a letter to governors dated 27 August, Robert Redfield, the director of the US Centers for Disease Control and Prevention, said states “in the near future” will receive permit applications from McKesson, a company which has contracted with CDC to distribute vaccines to places including state and local health departments and hospitals:

“CDC urgently requests your assistance in expediting applications for these distribution facilities and, if necessary, asks that you consider waiving requirements that would prevent these facilities from becoming fully operational by November 1, 2020,” Redfield wrote in a letter obtained by the Associated Press and McClatchy.

Presidential Election is November 3.

The ambitious timeline has raised concern among public health experts about an “October surprise” – a vaccine approval driven by political considerations ahead of a presidential election, rather than science.

Healthcare workers, national security employees and other high-risk groups would receive the first round of vaccines, according to guidance from the CDC.

Several vaccine and public health experts pointed out that final stage trials of experimental vaccines are still recruiting, and are at best halfway through that process. The vaccines are two doses, and each is given a month apart. Several experts told the AP they did not understand how there could be adequate data on whether the vaccines work and are safe before 1 November.

“Being ready is reasonable. Cutting short phase 3 trials before you get the information you need isn’t,” said Dr Paul Offit, a Children’s Hospital of Philadelphia immunization expert who sits on the FDA’s vaccine advisory committee.

... “It gives the appearance of a stunt rather than an expression of public health concern,” Hotez said.

Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: September 01, 2020, 05:31:54 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

August 31st, 2020:
     3,943,313 km2, a drop of -51,770 km2.
     2020 is 2nd lowest on record on this date.
     Highlighted 2020 & the 4 years with a daily lowest min in Sept. (2012, 2019, 2016 & 2007).
     In the graph are today's 10 lowest years.

P.S. 2020 became the second lowest minimum on record today. There are still about two weeks left until the 2020 melting season ends.

Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 18, 2020, 10:24:14 PM »
“you can't really tell, but we are looking at a quite different presentation”
Indeed. A major refinement and a very troubling new picture of the current state of the ice (assuming accuracy). The ice looks just terrible today along atlantic side … and elsewhere (gold areas in 2nd frame; click for full size and both frames):

Arctic sea ice / Re: The 2020 melting season
« on: August 17, 2020, 12:18:29 AM »
The awi amsr2 presentation, currently under development, has been available for 10 days. Here is a preview of CAA ice drift (aka garlic press) using the test version. aug6-15

Arctic sea ice / Re: The 2020 melting season
« on: August 02, 2020, 04:29:49 PM »
I made little animations using the NSIDC comparison tool comparing the remainder of the melting seasons 2012 and 2019 against the current state.

Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 11:01:41 AM »
We have got to stop using that old DMI chart. There are better available now. Moyhu, for instance has a better one.

Since this was mentioned in passing I thought people might like to look at it

It's not available for other years  :(.

Consequences / Re: COVID-19
« on: July 29, 2020, 01:54:06 AM »
A bit of humor....

Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 11:49:26 AM »
Concentration for the 26th, 27th and both combined.

Arctic sea ice / Re: The 2020 melting season
« on: July 26, 2020, 04:50:31 PM »
Cloud was light over the Beaufort yesterday, allowing a view of its center.  Rubbly ice over much of the entire sea, and ice is notably sparse in the middle of the sea.

Image pushed strongly for contrast on photoshop.

Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 06:04:20 PM »
I believe this more of a coincidence than meets the eye. In normal years the deep Beaufort is much emptier of ice, the shallower ESS often has lots of ice at this stage. And this year the deep Laptev/CAB sector is ice-free.
amsr2-uhh overlaid onto gmrt bathymetry, minimum jaxa dates, 2012-2018
must add 2019 sometime.
edit:Perhaps someone will put together all the nsidc minimums one day. I think they go back a lot further. If they do, I will attempt to overlay them onto bathy.

Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 07:28:03 AM »
July 20-24.


Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 07:07:44 AM »




Here is 144-268 h5 every 24 hours.

And 3 days of 850MB temps.

The wind  coming off NA hitting the Beaufort 11and Western CAB is Southerly with INSANE HEAT.

Arctic sea ice / Re: The 2020 melting season
« on: July 19, 2020, 07:00:43 PM »
Sea ice & bathymetry.

Arctic sea ice / Re: The 2020 melting season
« on: July 16, 2020, 06:01:49 AM »
The result could be storms at depth, size, and power we have never seen as humans.

Trying to push sub 900mb.

Bringing 75-115KT sustainable winds over huge parts of the Arctic.

Bringing massive swells and waves along a 2000 mile fetch slamming INTO Atlantic side ice.

Sounds pretty cinematic Friv, maybe we could collaborate on a film script sometime soon. I mean, not like today, but maybe tomorrow... or the day after.

Arctic sea ice / Re: The 2020 melting season
« on: July 15, 2020, 07:59:40 AM »
July 10-14.


Arctic sea ice / Re: The 2020 melting season
« on: July 10, 2020, 11:16:52 PM »
I don't usually have anything relevant to add here, but this came out today and seems to be topical ...

Arctic Ocean Changes Driven by Sub-Arctic Seas

New research explores how lower-latitude oceans drive complex changes in the Arctic Ocean, pushing the region into a new reality distinct from the 20th-century norm.

The University of Alaska Fairbanks and Finnish Meteorological Institute led the international effort, which included researchers from six countries. The first of several related papers was published this month in Frontiers in Marine Science.

The Arctic Ocean, which covers less than 3% of the Earth's surface, appears to be quite sensitive to abnormal conditions in lower-latitude oceans.

"With this in mind, the goal of our research was to illustrate the part of Arctic climate change driven by anomalous [different from the norm] influxes of oceanic water from the Atlantic Ocean and the Pacific Ocean, a process which we refer to as borealization," said lead author Igor Polyakov, an oceanographer at UAF's International Arctic Research Center and FMI

This conceptual model shows the influx of Pacific and Atlantic water into the Arctic Ocean in the past compared to recent years. Blue indicates cool water and red indicates warm water. Arrows indicate the direction of water flow.

Since the first temperature and salinity measurements taken in the late 1800s, scientists have known that cold and relatively fresh water, which is lighter than salty water, floats at the surface of the Arctic Ocean. This fresh layer blocks the warmth of the deeper water from melting sea ice.

In the Eurasian Basin, that is changing. Abnormal influx of warm, salty Atlantic water destabilizes the water column, making it more susceptible to mixing. The cool, fresh protective upper ocean layer is weakening and the ice is becoming vulnerable to heat from deeper in the ocean. As mixing and sea ice decay continues, the process accelerates. The ocean becomes more biologically productive as deeper, nutrient-rich water reaches the surface.

By contrast, increased influx of warm, relatively fresh Pacific water and local processes like sea ice melt and accumulation of river water make the separation between the surface and deep layers more pronounced on the Amerasian side of the Arctic. As the pool of fresh water grows, it limits mixing and the movement of nutrients to the surface, potentially making the region less biologically productive. ...

Vertical profiles of winter (NDJFMA) potential temperature (θ, left column, °C, A,C,E,G) and salinity (S, right column, psu, B,D,F,H) for the central points of the four selected regions of the Arctic Ocean (regions are identified in the right column, their geographical locations are shown in Figure 1) from the 1970s (blue) and 2000s-2010s (red). CHL, NSTM, PSW, and PWW identify Cold Halocline Layer, Near-Surface Temperature Maximum, Pacific Summer Water and Pacific Winter Water.

Igor V. Polyakov et al, Borealization of the Arctic Ocean in Response to Anomalous Advection From Sub-Arctic Seas, Frontiers in Marine Science (2020).

Pages: [1] 2 3 ... 10