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Messages - edmountain

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Consequences / Re: COVID-19
« on: March 23, 2020, 06:42:12 PM »

Letting it burn thru without masks on is not a plan at all.
The issue is that there is a shortage of masks. There are simply not enough to go around; thus somebody has to go without.

To illustrate this, consider a population of three people: a doctor, a nurse, and yourself. There are only two masks. Who gets the masks?

More importantly, how do you decide who should get them? Should they go to the people who move fastest and speak loudest or should they be allocated according to the best available evidence?

Consequences / Re: COVID-19
« on: March 23, 2020, 04:10:44 AM »
Can everyone cutting and pasting from journal articles please mind their exponents? The quoted "from 103.7 to 100.6" is three orders of magnitude different from the actual change in the article which was from 103.7 to 100.6 (otherwise known as from 5011 to 4 in linear terms).

Consequences / Re: COVID-19
« on: March 20, 2020, 03:05:08 PM »
From reddit...
Archimid, as a front-line healthcare worker I appreciate your concern for my welfare. However, since your opinions are obviously based on indiscriminate disregard of evidence I will choose to end this exchange with a simple thank you and best wishes.

Consequences / Re: COVID-19
« on: March 19, 2020, 05:41:05 PM »
First point:

SARS-CoV-2 remained viable in aerosols throughout the duration of our experiment (3 hours), with a reduction in infectious titer from 103.5 to 102.7 TCID50 per liter of air. This reduction was similar to that observed with SARS-CoV-1, from 104.3 to 103.5 TCID50 per milliliter

For three hours this virus can remain viable in the air if the physics of the room allow it.
Three hours was the limit of the experiment so it could be longer.

The second point, the air is the path of transmission for every nCoV infection unless the patient licks a surface. The virus is excreted in macro and microscopic particles every time a patient exhales, laughs or coughs.  From there it can land on surfaces to be picked up. That's when handwashing can help. But it can never fall to the ground before being breathed by another human.
Archimid, your copy and paste from the NEJM has an important formatting issue: you lost the powers of 10. The titers went from 103.5 to 102.7 (in linear terms from 3162 to 501) per milliliter of medium.

That said, the findings do indicate that airborne spread is plausible. However, you need to consider how the particles get aerosolized in the first place. It does not appear to happen everytime the patient "exhales, laughs or coughs." Rather,  aerosolization is far more likely to occur in hospital settings during certain procedures such as endotracheal intubation. That is why members of the general public need to stop hoarding N95 masks and allow the healthcare workers who need them to get them.

Consequences / Re: COVID-19
« on: March 18, 2020, 04:14:52 AM »
Better late than never.  Chloroquine (and Kaletra and remdesivir) have been positively recommended by clinicians in China for many weeks.  SKorea has positively recommended hydroxychloroquin and Kaletra.  Both have recommended starting use early in the course of infection.  WHO, CDC, and ECDC have been recommending against antiviral use.

I'm concerned that authorities may have slow-walked these options, in favor of Gilead's remdesivir, an investigational, high-cost, high-profit drug.  It won't be available until it's FDA-approved.  Profit motives may be responsible for the delay.

The other two are already FDA-approved (for other diagnoses) so there's no bureaucratic obstructions to using them immediately.  For other diseases, "off-label" use of medications is routine, when there are expert recommendation to support the use.  Waiting for completion of peer-reviewed, double-blind, placebo-controlled trials is inexcusable.  Many are dying because of this foot-dragging.
We're actively talking about this at a provincial level in Alberta and it's not as simple as it may seem. All of the medications you mentioned are in very limited supply. We only have enough lopinavir/ritonavir to supply the HIV patients their current needs but no more. There's some hydroxychloroquine but not in pandemic amounts as it's largely procured for use in autoimmune disease (Alberta not being a malaria endemic area). There's basically no chloroquine if someone were hoping to use that instead. Needless to say there's also very little remdesivir which is, as you say, expensive and experimental.

There's a lot of constraints on the system, especially for supply lines. We're struggling even with simple things like N95 masks and NP swabs let alone medications. As much as people want to try things that might help, supply lines can't just be easily ramped up overnight. In many cases it may actually be easiest to get medications is through a clinical trial. That obviously doesn't help everyone right away but at least it generates knowledge.

That said, supply lines could be ramped up if there were clear evidence of benefit. However, just being in the somebody's guidelines doesn't cut it. Things actually make it into guidelines all the time without any supporting evidence: just look at what the IDSA guidelines say about the treatment of influenza with oseltamivir then look at the evidence.

Consequences / Re: COVID-19
« on: March 18, 2020, 01:03:29 AM »
^ it's a mathematical model based on mobility data, not testing.
That Science paper (which has now been mentioned at least 4 times) is just one of several independent lines of evidence suggesting that there are in fact a large number of undocumented cases.

The fact that the paper in question is based on a model does not in and of itself invalidate its findings. Are you so quick to dismiss evidence stemming from mathematical models in other fields, for example climate science?

Consequences / Re: COVID-19
« on: March 16, 2020, 05:06:21 PM »


U.S. May Need 6-8 Weeks to Get Over the Worst (7:30 a.m. NY)

U.S. Surgeon General Jerome Adams says the nation may need six to eight weeks to get over the majority of coronavirus-related pain, if the situation develops as it did in China and South Korea.

Adams, speaking on Fox News, acknowledged there is a chance the U.S. does worse than South Korea, and that the situation could get as bad as in Italy.

Given that testing in the US has been so badly botched they will be extremely lucky to get an outcome anywhere near that of China or South Korea. Based on deaths, which are presumably easier to track than cases, it seems likely that the current number of cases in the US is at least the same as South Korea, i.e. around 8,000. Frankly, even that may be an underestimate: it's possible people have died in the US without having been tested so the actual number of deaths could be even higher.

Consequences / Re: COVID-19
« on: March 15, 2020, 09:58:04 PM »

The difference in 1-4% fatal isn’t with medical folks. They get it. They focus on what is right before them and what is important.

The importance is with the political leaders. When they fall into the threshold belief that this is just another flu, that is when they fail to act and fail to act quickly enough or massively enough. That is when a simple disease outbreak becomes an epidemic and when an epidemic becomes a pandemic.

In the end, the CFR will be a footnote. Unfortunately it will be a footnote to a paragraph that explains how leaders were so stupid as to allow a pandemic to ravage the world killing untold millions, and about how unnecessary those deaths were, and where it was that they got this idea from.

That is why and where the CFR argument has any importance at all. That - and the lives destroyed by all of those individual unnecessary deaths.

Sam, I think we're both on the same side in that we're each trying to achieve the best possible outcome under the circumstances. Your concerns are clearly genuine, heartfelt, and admirable. However, I feel our personal and professional circumstances are leading to different approaches as to how a good outcome could be achieved.

I don't want to be self-aggrandizing but I feel compelled to reiterate that I work within the medical system on the front lines clinically, at the operations level through management, and in my academic role. Through my work and research I know firsthand what the scientific consensus on this issue is. The consensus is that the CFR is only one small piece of the puzzle. Whatever its eventual value, it is clearly dangerously high; I have not a single colleague who believes that this is "just another flu".

More important than the numerical value of the CFR though is the realization that it is modifiable through application of evidence-based interventions [see edit below]. Discussion focused on the response and the evidence available to guide this response is, in my opinion, of far greater value than continual bidding wars about a fuzzy number.

Edit: what I should have said above is that the total number of cases and whence the number of deaths is modifiable; the CFR in and of itself is not modifiable. Apologies for the error.

Consequences / Re: COVID-19
« on: March 15, 2020, 07:13:54 PM »

Any references on the upregulation of ACE2 by ACE-inhibitors and ARBs?  I'm not doubting you, but I'd looked into this question and didn't find a clear answer.

It's of more than academic interest, as I have HTN and am on an ACE inhibitor.  I'm probably not alone on this forum in this regard.
Most of the evidence is based on extrapolation from animal models:

For humans the evidence is less clear and somewhat contradictory:

It's probably not as cut-and-dry as the Lancet Respiratory letter suggested and that's a valid criticism of their position--and a weakness that I further perpetuated by reposting it verbatim here! This is an active area of inquiry that's moving at a pace not general seen in the internal medicine community. Matthew Sparks from Duke and Swapnil Hiremath out of Ottawa are doing their best to stay on top of things over at the nephrology journal club.

Take home message is: don't listen to some hack on the internet. Instead, speak to your doctor.

Consequences / Re: COVID-19
« on: March 15, 2020, 02:12:59 AM »
The test are useful for contact tracing and epidemic management. If contact tracing is not possible, then a quarantine is the answer. Take the hit for a 3-4 weeks, start tracing again when the numbers go down.

Right now they are taking the most costly route in terms of lives and money. Is not that they are greedy. They just don’t know what they are doing.
Testing has another important role which is to exclude covid-19 in those patients presenting with an influenza-like illness so that they can avoid being in isolation for 2 weeks or more and get back to being productive members of society. This is particularly important for health care workers.

However, the test is only useful in this regard for low pretest probabilities. If the numbers from New York that Alexander posted are accurate then the pretest probability in that sample is actually quite high; the test is therefore not helpful at excluding the disease in those individuals.

As you suggested: they seem to have botched it.

Consequences / Re: COVID-19
« on: March 09, 2020, 01:31:52 PM »
For people here following the science side of this virus, the best two resources are biorxive (hasty preprints) and pubmed (final peer-reviewed), not so much press releases from know-nothing campus publicists or pharma marketing promotions of pre-existing repurposed miracle drugs (possibly with rush-rush clinical trials and carcinogenic side effects).


For those of us who deal with the clinical side of things there's also the medRxiv preprint server.

Consequences / Re: COVID-19
« on: March 09, 2020, 03:13:11 AM »
Linear growth in South Korea rather than exponential for a week now, that's some glimmer of hope at least.

Consequences / Re: COVID-19
« on: March 08, 2020, 11:47:10 PM »


Oil now a ‘bigger problem for markets than the coronavirus,’ analyst says

Oil prices plunged last week as OPEC and its allies failed to reach an agreement on production cuts, and as prices look set to continue cratering, some are warning about the impact on the broader economy.

“Crude has become a bigger problem for markets than the coronavirus,” Vital Knowledge founder Adam Crisafulli said Sunday. “It will be virtually impossible for the [S&P 500] to sustainably bounce if Brent continues to crater,” he added.

Oil has absolutely tanked as Asian markets opened. This is incredible... Down more than 20%!


Consequences / Re: COVID-19
« on: March 07, 2020, 04:29:27 AM »
The US CDC is now recommending that those over 60 or with serious health conditions stay home.

Let's hope people follow their advice! Although their actual advice was "stay at home as much as possible" so rather open-ended. And they didn't actually specify the age of 60, just "older adults". Most people would probably just interpret that as "anyone older than me".

Consequences / Re: COVID-19
« on: March 07, 2020, 04:20:30 AM »
'Wildly Unprepared’: Survey of US Nurses Highlights Coronavirus Concerns


Just 63% of nurses surveyed had access to N95 respirators in their units, while a mere 27% had access to powered air purifying respirators.

The clamor over N95 masks is a good example of the problems that arise when decisions are made based on fear rather than on evidence. In my health region we are faced with a growing concern regarding the supply of N95 masks--a looming shortage that would possibly be completely avoidable if their use elsewhere were reserved only for when they are really needed rather than universally.

Elsewhere in Canada, the Ontario Ministry of Health was recently taken to task by ID doctors over similar concerns.
Ontario’s coronavirus policy for health workers not supported by evidence, experts warn

Ontario’s policy for protecting health-care workers against COVID-19 wastes precious resources and leaves hospitals unable to safely cope with an expected rise in coronavirus patients in the coming days, infectious disease experts warn.


But numerous infectious disease experts say mounting evidence shows COVID-19 spreads through droplets, such as when an infected person sneezes and coughs, and that airborne precautions are not appropriate nor are they supported by evidence. Instead, they say health professionals should use “droplet precautions,” which refer to gowns, eye guards, gloves and regular surgical masks.


In other news, my region is about to start testing all patients presenting with ILI symptoms for SARS-CoV-2; no longer will a travel history or epidemiological link be required. I expect a big increase in cases soon (source: inside information).

Consequences / Re: COVID-19
« on: March 04, 2020, 03:14:34 AM »
WHO chief, arguably the world's top 'authority' in such matters:

"We are in unchartered territory.

We have never before seen a respiratory pathogen that is capable of community transmission..."

That is an extremely misleading selective quotation you have just provided. The full statement from Director-General Ghebreyesus was:

"We have never before seen a respiratory pathogen that is capable of community transmission but which can also be contained with the right measures."


Consequences / Re: COVID-19
« on: March 03, 2020, 09:18:59 PM »
Health system in northern Italy stretched to the limit. 10 % of medical staff already infected.
From the article:

Alarmingly, 10% of Lombardy’s doctors and nurses cannot work because they tested positive for the virus and are in quarantine, the region’s top health official, Giulio Gallera, said Monday.

I can't help but think that something was lost in translation. Italy has about 10.7 doctors and nurses per 1,000 people (source), hence probably about 107,000 doctors and nurses among Lombardy's 10 million inhabitants. If 10% have tested positive that's more than 10,000 cases just from doctors and nurses!

Consequences / Re: COVID-19
« on: March 03, 2020, 03:42:11 PM »
That is perhaps true if you are a health care worker who will be repeatedly exposed thousands of times, and who doesn’t mind risking ultimate exposure, illness, heart damage, lung damage, kidney damage, and death.

Yes sure, in that case, by all means use the piss poor protective recommendations from CDC. While you are at it, rely on their seemingly mostly ineffective test. 

What a strangely angry response. If the CDC IPC guidelines are "piss poor" I am curious what you think of the guidelines from the WHO, Health Canada, and other jurisdictions which are actually less strict than those from the CDC.

Consequences / Re: COVID-19
« on: March 03, 2020, 03:14:36 AM »
Archimid's picture is probably all too real . I watched in disbelief what was obviously someone being transferred from old folks home to ambulance in Washington 24+ hours ago .. pretty sure it was on bbc .. again no precautions beyond basic masks . If that's the USA's preparedness I guess someone has calculated if you are going to lose the pensioners , may as well get the carers off the payroll too .. b.c.
Interestingly the CDC guidelines for infection prevention and control for COVID-19 seem to be more strict than most other jurisdictions. CDC recommend N95 masks and negative-pressure isolation at all times. WHO guidelines recommend N95 masks and negative-pressure isolation only when aerosolizing procedures (e.g., endotracheal intubation) are being performed; at other times a regular medical mask can be used. Canadian guidelines are roughly parallel to WHO guidelines.

The WHO guidelines actually make more sense given what we know about the mechanism of transmission of this disease. N95 masks and negative-pressure isolation rooms are valuable resources and need to be used rationally.

WHO guidelines for IPC:

Health Canada:


Consequences / Re: COVID-19
« on: March 02, 2020, 10:52:39 PM »
That did not come out of nowhere. Read some of the earlier posts about the US healthcare on this thread. Get tested for flu costs 4k$ and many can not pay that which will make the outcome worse also because of additional community spread.

Yes, to us on this thread it did not come out of nowhere, but for the general public it did. Death rate for confirmed US mainland cases is now over 10%.  And yes, the real death rate if probably much lower due to more cases out their waiting to be confirmed.
All six deaths occurred at EvergreenHealth Health hospital in Kirkland including two clients of the Life Care long-term care centre where an outbreak was confirmed. There's a pretty good chance that all deaths end up being connected to the long-term care centre somehow. Regardless, there's very soon going to be a large uptick in the number of cases both confirmed and unconfirmed in the Seattle area.

Also given, what we know about who disease affects most, there's likely to be a quick uptick in the number of fatalities. Residents of long-term care facilities are vulnerable at the best of times.

Consequences / Re: COVID-19
« on: March 02, 2020, 02:40:45 AM »
I am not an expert but I think your logic is flawed.
If a reduced immune response is partly why children are less affected is the reason they are okay, then it stands to reason that those with suppressed immunity would be the same way and it would also hit those with health immunity harder.
The immune system is not a single anti-infectious process, it's more a collection of processes some of which are pro-inflammatory causing cellular injury and some of which are anti-inflammatory and promote cellular repair. In health, these processes balance each other out. In sepsis, this balance is disturbed leading to loss of homeostasis, multi-organ failure, and, frequently, death.

People with immune dysfunction, such as those with increased age, chronic disease, malignancy, etc are more prone to sepsis not necessarily because their immune systems are "reduced" but because their equilibrium between pro- and anti-inflammatory processes is more unstable.

Consequences / Re: COVID-19
« on: March 01, 2020, 05:32:46 AM »
For those interested in reviewing the peer-reviewed literature describing the clinical characteristics of this virus, most major journals are allowing free access to relevant papers. For example, yesterday the New England Journal of Medicine published data from a series of 1099 hospitalised and confirmed cases through January 29.

The median age of the patients was 47 years; 41.9% of the patients were female. The primary composite end point occurred in 67 patients (6.1%), including 5.0% who were admitted to the ICU, 2.3% who underwent invasive mechanical ventilation, and 1.4% who died. Only 1.9% of the patients had a history of direct contact with wildlife. Among nonresidents of Wuhan, 72.3% had contact with residents of Wuhan, including 31.3% who had visited the city. The most common symptoms were fever (43.8% on admission and 88.7% during hospitalization) and cough (67.8%). Diarrhea was uncommon (3.8%). The median incubation period was 4 days (interquartile range, 2 to 7). On admission, ground-glass opacity was the most common radiologic finding on chest computed tomography (CT) (56.4%). No radiographic or CT abnormality was found in 157 of 877 patients (17.9%) with nonsevere disease and in 5 of 173 patients (2.9%) with severe disease. Lymphocytopenia was present in 83.2% of the patients on admission.

Consequences / Re: COVID-19
« on: February 26, 2020, 02:52:20 AM »
If that is true (I.e. that the blue and gold bars represent the same set of patients), then it is clear that a large subset of patients not counted in these bars and represented by the as yet missing right tail of the gold bars will when counted increase the counts in the blue bars shifting the distribution to the right as they are counted.

The data as presented in the synopsis is not (at least at first reading) absolutely clear which case is true. 1) that the blue bars represent all cases reporting with symptoms, or 2) that the blue bars only represent those cases presenting with symptoms that are later confirmed.

The rest of the analysis is unchanged. The death count is incomplete, as is the recovery count.

The graph represents 44,672 confirmed cases. Of these almost 90% had onset of illness by January 31. The "death count" while not complete is going to be pretty close.

Consequences / Re: COVID-19
« on: February 25, 2020, 10:52:06 PM »

In a word - wrong.

Note that the blue bars are about new incidence. And yes for this cohort, new incidence is nearing an apparent end.

But note then the gold bars - confirmed. That count is about 2/3rds complete due to the delay in testing compared to symptomoligy.

Sam, you misread the graph. All cases are confirmed.

Consequences / Re: COVID-19
« on: February 25, 2020, 10:00:38 PM »
I too find the poll rather shameful and wish it were taken down.

With respect to the earlier discussion about the case fatality rate (CFR), it's safe to say that the authors of that JAMA paper are well and truly aware of the pitfalls of measuring the CFR when things are still evolving. That said, the CFR estimate they provide is specifically for that series of cases and for that series the number of new cases was virtually nil by February 11 as evidenced by the height of the blue bars from their Figure 1.


Whence given what we know about the duration of the disease I think it's unlikely the overall CFR will be significantly higher than the 2.3% for this series of cases. Indeed, the authors discuss the foibles of estimating the CFR and provide good reasons why it might actually be lower than this:

As of the end of February 18, 2020, China has reported 72 528 confirmed cases (98.9% of the global total) and 1870 deaths (99.8% of the global total). This translates to a current crude CFR of 2.6%. However, the total number of COVID-19 cases is likely higher due to inherent difficulties in identifying and counting mild and asymptomatic cases. Furthermore, the still-insufficient testing capacity for COVID-19 in China means that many suspected and clinically diagnosed cases are not yet counted in the denominator. This uncertainty in the CFR may be reflected by the important difference between the CFR in Hubei (2.9%) compared with outside Hubei (0.4%). Nevertheless, all CFRs still need to be interpreted with caution and more research is required.

Consequences / Re: COVID-19
« on: February 09, 2020, 08:17:05 PM »

If for example we take the current daily growth factor as being 1.32 and the mean time from confirmed status to death, we would expect the value of the ratio of the number dying each day to the number confirmed each day to be about equal to the inverse of 1.32^6 times the case fatality rate. 1/(1.32^6) equals 0.189.  If as we seem to be seeing, the mean death rate is 10-12% of those infected and reporting to hospital, then we would expect the ratio of daily deaths to daily confirmations to be about 0.019 to 0.023 (1.9%-2.3%). If the CFR is 11%, the ratio would be ~2.1%

Thank you for this helpful post.

When calculating the CFR I'm not sure it's necessary to estimate an exponential growth rate which is then used to calculate the number of cases 6 days ago. Rather, one can simply use the directly measured number of cases from 6 days ago. This would reduce the number of parameters in your model to just one, i.e. the estimate of the 6 days for the time from confirmation to death.

Consequences / Re: COVID-19
« on: February 09, 2020, 01:09:08 AM »
The contagiousness and significant lethality of this virus are roughly comparable to the 1918 influenza pandemic.  Similarly to that episode, there is currently no available vaccine or antiviral treatment.  Unlike that episode, we have a good diagnostic test, though test availability is still terribly limited.

Also unlike 1918 pandemic, we have prospects of finding effective anti-viral treatment in a matter of perhaps weeks.  But actually making a new medication available around the world to all who become sick will takes many months of dedicated, funded, herculean efforts.  Wealthy nations and individuals will, of course, be first in line.
One interesting thing about the 1918 influenza epidemic was a disproportionate number of deaths among seemingly-healthy 20-40 year-old individuals; the mortality curve was W-shaped rather than U-shaped. These deaths accounted for the majority of "excess" influenza deaths over the course the pandemic (source).

Thus far it seems as if the Wuhan coronavirus is not following this 1918 influenza pattern: the most severely ill and the most fatalities seem to be older or comorbid individuals. See, for example, this case series of 138 hospitalized patients recently published in JAMA.

Also unlike 1918 pandemic, we have prospects of finding effective anti-viral treatment in a matter of perhaps weeks.  But actually making a new medication available around the world to all who become sick will takes many months of dedicated, funded, herculean efforts.  Wealthy nations and individuals will, of course, be first in line.
Another interesting thing about the 1918 influenza pandemic was that a large part of excess influenza deaths were caused secondary bacterial pneumonias (source, and references therein) for which no effective treatment, i.e. antibacterials, existed in 1918. If secondary bacterial pneumonias comprise an important complication of the current infection then antibacterials may be of benefit. This is of course a big if but it's notable that most of the patients in the JAMA case series above received antibacterials. Obviously antibacterials have no role in treating the primary infection

What this means exactly for the future transmission of the Wuhan virus remains to be seen. As you suggest, there are many reasons to believe that the current outbreak will not automatically be a repeat of 1918.

Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: February 04, 2020, 10:52:09 PM »
January 2020 Warmest On Record: EU Climate Service

Last month was the warmest January on record globally, while in Europe temperatures were a balmy three degrees Celsius above the average January from 1981 to 2010, the European Union's climate monitoring system reported Tuesday.

These data would seem to be more empiric and less "weird and anecdotal"--which makes it all the more concerning.

Antarctica / Re: Thwaites Glacier Discussion
« on: February 03, 2020, 06:38:06 PM »


2°C above freezing, so that would be....? Is that 0.2°C (assuming saltwater at -1.8°C) or 2°C? The latter is scary, the former, that's not much above the melt point of the freshwater glacier. Basically an order of magnitude less energy to melt the glacier. that 10x difference may become important....

The attached image shows comparable measurements taken beneath the Pine Island Ice Shelf several years ago; and to me it is clear that the 2oC is above the freezing temperature of seawater under pressure.  No other interpretation makes any sense.
This interpretation is supported by an article from the Washington Post where the temperature measurement is reported in a less-ambiguous fashion.

At a region known as the “grounding line,” where the ice transitions between resting on bedrock and floating on the ocean, scientists measured water temperatures of about 0 degrees Celsius (32 degrees Fahrenheit). That is more than 2 degrees warmer than the freezing point in that location, said David Holland, a New York University glaciologist. He performed the research with Keith Nicholls of the British Antarctic Survey.

Consequences / Re: COVID-19
« on: February 03, 2020, 05:11:34 PM »
I find it interesting that this thread, covering one infectious disease, in a matter of days, has accumulated more posts than its parent thread, covering all infectious diseases, accumulated in a matter of years.

This thread has really brought the anti-science doomer contingent out of the woodwork.

Consequences / Re: COVID-19
« on: February 02, 2020, 12:54:53 AM »
As per the official notification from the Chinese government (as translated by google) it seems as if this H5N1 outbreak is already over (the usual caveats regarding any information provided by the Chinese government obviously apply).


In addition to bird to human transmission, flu is transmitted human to human. Just like the corona virus this might be slowed by human interventions. But with a simultaneous pandemic with corona virus the results may be chaotic. People with symptoms of fever and vomiting could be either disease. That makes things very hard for the health care workers, right up until the system is completely overwhelmed. At that point in a pandemic, people will mostly need to fend for themselves at home.

Fortunately though human-to-human transmission of H5N1 has been found thus far to be inefficient.


The one advantage with H5N1, is that if the human to human transmission can be slowed enough or stopped, there may be time to begin a mass vaccination campaign against it. The vaccines exist now. But they may require months to be produced targeted at the pandemic version of the virus.

Yes but although the vaccines exist, their effectiveness is limited by their modest immunogenicity and the antigenic diversity of H5N1 circulating virus. However, oseltamivir may be of some help in both prophylaxis and treatment.

1. You misinterpret my posts.  We need to get off of fossil fuels fast. 

What I'm saying is that we're doing that.
Your optimism is admirable but I have not seen any data to suggest the world is getting off fossil fuels fast. The only data I have seen suggests that fossil fuel consumption is rising year after year. This is borne out by the inexorable and accelerating climb in CO2 levels as shown by KiwiGriff.

Also, you tend to completely ignore facts that make the extreme right tail risks unlikely to occur.  Case in point, renewables have been less expensive than coal for almost two years now.  Investments in new coal plants have plummeted and retirements of coal power plants have accelerated.  Coal use is projected to peak within a few years and then rapidly decrease afterwards.  Even thought that's been pointed out, you seem to think that we'll still be on the RCP 8.5 scenario when there is no other source of greenhouse gas emissions that can make up for the missing coal emissions.
Alas, projections are not facts. And there are plenty of other sources of GHG emissions to replace coal.

Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 11:34:51 PM »
i'd say we can safely settle on very approximate range of ~180...300 W/m2 absorbed at the surface under clear skies (high pressure systems) for late July / early August

So about 5-9 cm of ice per day might be melting under the clear skies of the big high pressure system soon to arrive in the CAB.

Reason: it takes about 35 W/m^2 to melt each centimeter of ice per day:

Energy flux to melt 1 cm thickness of ice per day [in units of W/m^2] = 1 cm x (10^4 cm^2/m^2) x (334 J/g latent heat of melt) x (0.9 g/cm^3 density) / ( 3600x24 seconds/day)
= 35 W/m^2

(Uses the definition W = J/s)


Doesn't that seem a bit high? Let's say, roughly speaking, that the Arctic sea ice is observed to lose on average about 2 cm per day (that's 200 cm over a 100 day melt season).

Then that's 70 W/m^2 delivered to the ice on average from all sources combined: sun, air and water.

Is that compatible with the insolation plot shown - where 'clear skies' are presumed to add 180-300 W/m^2 - and that is for more than a month past the Summer solstice?

If we believe '180-300 W/m^2' then it seems like only a small fraction of 'clear skies' over the ice would use up the energy budget to produce the amount of melt we observe.

So I'm skeptical that all the insolation shown in the plot actually does get to heat up the ice, even under 'clear skies'.

Asking the experts then: is that insolation plot for the top of the atmosphere and, further, is a considerable fraction of that energy lost even under what we consider to be 'clear skies'?
If I'm not mistaken, your calculation assumes the ice is already at a temperature of 0°C.

Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 09:11:25 PM »
Insolation at 90 degrees is greater than at the Equator until the first week in August.

Ought to settle this question.
Except that the albedo of the underlying surface is in large part a function of the angle of incidence of the solar radiation. This is true not just for water but also for sea ice.

Source: Hudson, 2011

At 90°N latitude at this time of year the solar zenith angle is about 70° so that all the time is spent in the high-albedo part of the curve. South of 30°N, once the sun rises, almost all daylight hours have a solar zenith angle less than 70° and for much of the day less it's than 40°; at tropical latitudes it can obviously reach 0° at high noon. The end result is a great deal of time is spent in the low-albedo part of the curve.

I have no idea how to quantify this difference. My point is that it's not as simple as calculating the theoretical 24-hour solar insolation based on latitude alone and calling it a day.

Arctic sea ice / Re: The 2019 melting season
« on: July 14, 2019, 09:42:32 PM »
In terms of melting that multi-year ice in the CAA and CAB, I just noticed that CFS Alert, Nunavut, at the top of Ellesmere Island latitude 82°N and on the edge of the Arctic Ocean has today equaled their all-time record high of 20°C. This is just an hourly reading (and it reached it twice) so there's a very good chance of an all-time record.

Further south on Ellesmere, Eureka has been well above average all month with a mean temperature of 8.6°C (normal 6.1°C). Eventually this heat will have an impact on the ice.

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