Warm weather and CV
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Started by pj - May 21, 2020, 2:54 p.m.

With the number of cases now rising rapidly in Brazil, Mexico, India and Montgomery, AL, it doesn't appear that warm weather is much of a deterrent to the spread of CV. 

By metmike - May 21, 2020, 4 p.m.
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This is a great point pj. Glad you brought it up and this fact, (flu outbreaks in the tropics) which seems to also happen with the seasonal flu in most years has puzzled many and caused some to think that maybe there isn't any affect from heat/humidity.

What I feel confident in, after spending hours reading every study I could find earlier in the year is that increasing the humidity, decreases the survival time of the virus.

The results were pretty conclusive in the laboratory, so for me, its a scientific fact. Basically, if you double the humidity, you decrease the amount of virus that survives for 1 hour by 50%.  Temperatures did not matter and its not relative humidity but absolute humidity that matters most(dew points). 

                Coronavirus and weather-Wonderful News!            

                            29 responses |         

                Started by metmike - March 23, 2020, 10:58 p.m.            


But here is how this can be misleading. In most realms, if this were the MAIN factor, you would expect twice as many cases where the humidity was 50% lower...........higher latitudes in the Winter or even Las Vegas because your dew points/absolute humidity is extremely low. There may be some tendencies and often we see flu outbreaks several days following Arctic blasts...........but not always. 

So for sure this laboratory proven affect is super imposed on the environment. However, there are other powerful forces in play. In CV, if it's 4 times more contagious than the flu, then more humid weather might make it only 2 times as contagious as the flu..............in theory/speculation.

LESS contagious but doesn't wipe it out. Social distancing and wearing masks are probably much more powerful in stopping transmission rates than warmer much more humid air by doubling the humidity. In theory, it might make the other actions more effective though. That doesn't equate to half as many cases or twice as effective because only 50% of the virus is around after an hour. If most of the transmission takes place within minutes of being exposed to an infected person, the humidity is not going to play much of a role. 

I remember reading about the Tropics have a different flu season than the mid latitudes. It's always warm there of course. I'll go back and bring some studies up on it. It seems like it was happening during the rainy season. This might make it a bit more humid(but humidity might always be high and the difference negligable) but maybe people spend more time indoors and this becomes the main factor. 

In the mid latitudes, there is also more than humidity at play during the flu season. People do spend more time indoors.

By wglassfo - May 21, 2020, 4:07 p.m.
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The economic and cv picture has me deeply worried. I expect most people will just do as we are told and what ever happens, will happen. Most of us have decided long ago we can't do much, other than following guidelines, some common sense and that is about it

However, the economic picture should have us deeply worried. For every bit of good news, and there is some, the bad news over whelms the good news. Any kind of  re-opening guidelines have proven useless as no one size fits everybody. We might as well assume this virus will be with us and the world for a very long time. I doubt a vaccine which many people have hopes for, just isn't going to happen any time soon.

I consider the unemployment numbers the most important metric that will tell us the health and recovery of the economy.

So: In order to try and prop up our economy, until employment gets back to some sort of reasonable numbers and recovery is happening, the printing will continue,.  If we insist on closing down a business if corona is found in that work place. We will find corona all over, as fast as one business opens up another will close down. This will make recovery impossible

Did you know that if the banks suffer a 10% default on their loans, the banks are insolvent, as that is the total sum of the banks equity

Well: I expect the banks will own a lot of worthless property or assets as the payments are not made and the assets can not generate revenue, thus the value falls below the 10% level of value the loan was originally approved

If the Fed is forced to inject liquidity into the banks, plus all the never ending stimulas, how long can the system continue with all of this increasing Federal debt???

The gov't will take care of us until it can't

By metmike - May 21, 2020, 4:34 p.m.
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This has me deeply intrigued and I'll try to find more relevant information about it.

By metmike - May 21, 2020, 4:44 p.m.
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Influenza Seasonality in the Tropics and Subtropics – When to Vaccinate?


Periods of peak flu activity were identified for 70 of the 138 countries examined, representing about 73% of the world’s population. Thirty-seven countries had one distinct influenza peak and 17 countries had two distinct peaks each year. Countries near the equator often identify influenza throughout the year and had secondary peaks. Researchers determined that most countries in Central and South America, South and Southeast Asia experienced a primary period of influenza activity from April to June. India showed an additional secondary peak between October and December. Africa presented a complex picture with increased activity from October to December in the northern region, from April to June in the southern region and throughout the year in sub-Saharan countries near the equator.

By metmike - May 21, 2020, 4:52 p.m.
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Additional images:

Though the timing of the biannual influenza vaccine selection–production cycle has worked well for the temperate regions of the northern and southern hemispheres, its applicability to the seasonality seen in the tropics and subtropics is thought to be uncertain [25,26]. Our findings suggests that the optimal timing for the annual seasonal influenza vaccination campaign based on the start of the main influenza activity period, could be identified for most countries in the tropics and subtropics. Countries such as Brazil, China and India that have subnational variability in their seasonality pattern and countries situated near the equator with significant influenza activity throughout the year may need to consider alternate strategies based on their local seasonality

By metmike - May 21, 2020, 4:59 p.m.
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Based on just this, it appears that we are not going to find a clear weather related smoking gun to the seasonality.........or lack of it in some cases of virus's in the warm regions of the planet. 

I would now like to see if the number of cases and deaths are less in the tropics compared to mid latitudes.

On 2nd thought, this could be very misleading. The mid latitudes have alot of the high population centers which would be the perfect breeding grounds for a virus to spread vs the tropics, where less people live.

So finding less flu in the tropics could be from both factors, with population likely more important.

By metmike - May 21, 2020, 5:19 p.m.
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We hit the jackpot at this link!

What the chart below is telling us is the correlation with temp, solar radiation and specific humidity(absolute humidity/dew point) is more powerful as you go from 0 degrees latitude to 50 degrees latitude.

Relative humidity is a problem because in the Winter, you can bring in cold air with near 100%  relative humidity, heat it up  and have very low relative humidity. So forget that one. 

Also, precipitation correlates closely at the highest latitudes just because it drops off so much in the Winter and increases in the Spring and the correlation might be coincidental vs causation.

Also, the 3 factors that correlate so strongly, solar radiation, temperature and specific humidity all have the same causes(the angle of the sun outside) and will all move in tandem, so one of them could be the main reason for CAUSING the correlation with flu and the others could just be coincidental. 

Related to this, the stronger sun warms the air in the Spring, then the warmer air can hold more moisture. It's possible that the increased/decreased moisture in the air is most important to the flu but the other factors had to cause the air to be able to hold more moisture. 


Influenza peaks and climate by latitude. The mean monthly rank of each climate variable corresponding to the month of peak influenza for each 10 u latitudinal band. Solar radiation, temperature and specific humidity are lagged by 1 month. The background interval corresponds to the 95% null distribution. (A) displays the results for both primary and secondary influenza peaks; whereas (B) shows the results for primary influenza peaks only. Influenza peaks corresponded to months characterized by low ranks of temperature, solar radiation, and specific humidity in high latitudes. Primary influenza peaks corresponded to months with high ranks of humidity (both relative and specific) and precipitation in low latitudes. doi:10.1371/journal.ppat.1003194.g002 

By pj - May 22, 2020, 1:14 p.m.
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mm: Thanks for all your info, interesting stuff.


If this means via surfaces may not be a very likely way of transmitting the virus, maybe it helps explain why warmer temps don't seem as strong a factor in reducing the contagion.

Can't help myself here.

Feb 10 - “Looks like by April, you know, when it gets a little warmer, it miraculously goes away.” 

By metmike - May 22, 2020, 2:23 p.m.
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Can't help myself here.

Feb 10 - “Looks like by April, you know, when it gets a little warmer, it miraculously goes away.” 

I have an even better one pj:

"Anyone care to bet me that Coronavirus deaths will be  lower in almost every country of the world vs flu deaths that occur every single year?"

Can you guess who said that and when?

                Re: Re: Re: Re: Re: Re: Re: Coronavirus loony panic            

                            By metmike - March 9, 2020, 8:06 p.m.            


It was me!

But at least we barely got our huge, successful chess tournament in(with over 400 people crammed together on March 7th-5 days before the  shut downs here) in an atmosphere that is impossible to imagine now. 

                Wonderful Chess Tournament            

                            13 responses |            

                Started by metmike - March 2, 2020, 4:17 p.m.            


By pj - May 22, 2020, 3:13 p.m.
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Don't know if you were being serious about it being a "better one"? I tend to think not, since you're a modest guy.

But re: "I have high confidence, based entirely on the facts and science that we know with certainty, that at the end of 2020, deaths from coronavirus in the US will be a very tiny fraction of the deaths from the flu."

According to this  https://tinyurl.com/y7qulkrt 94,000 deaths so far from CV,  24,000-62,000 deaths from the flu.

Either way, would I ever prefer to have you (rather the unscientific, anti-science guy), going on TV day after day describing what's going on with cv.

By metmike - May 22, 2020, 4:11 p.m.
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I was just showing how 3 months ago, almost nobody, including me imagined how bad this was going to get and what path it would take(except for Wayne, who actually was pretty extreme).

Of course I wouldn't try to pretend otherwise and previous threads here are the evidence.

In early March, I was guessing 10,000 infections by the end of March. Not deaths but infections!

By mid-March, I adjusted that to 200,000 infections..........we ended up at 190,000 infections at the end of March. 

I was also extremely low on deaths for a long time as you might remember when I questioned how high your estimate was(you ended up closer for deaths than any model or prediction that I ever saw).

I stopped trying to guess the numbers well over a month ago, realizing this was not a field of my expertise where I had great skills..........other than things like knowing that CNN/NYT's pushing the 200,000/day at the end of this month 2 weeks ago wascomplete  bs. 

By metmike - May 22, 2020, 4:38 p.m.
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I'm still blown away by how lucky we were to get that chess tournament in, just days before the shut down.

I would have been stuck with $1,000 worth of trophies and have had to refund entry fees for almost 200 kids!

Since you've probably never been to an event like this, at the start of each of 6 rounds,  the pairings for all 4 divisions are posted in 4 different places as each round ends in each division.

When they are posted on the wall, there are many dozens of kids and parents smashed together(physically touching numerous people all around them the entire time) trying to get close to the wall to see their name, who they play and where they play. 

2 weeks after that, the SCI Scholastic Chess of Indiana team state championships was being held up near Chicago. They have something like 600 kids and over 1,000 people. It's the biggest chess event of the year in the state.

Same thing like our tournament X3!

A few days after we finished our tournament, from following the coronavirus here, I saw the writing on the wall for the SCI tournament and contacted the tournament directer to tell him I was so sorry. Things were not shut down yet and he must have been thinking that I was Mr. Pessimistic but holy cow, think of the environment that I just described. If they had just 1 event in the state of IN that they could shut down to prevent the spread...........that was it.

Kids from every part of the state all crammed together like sardines, 6 times,  then sitting next to each other(from a different school each time) playing chess for 8 hours. 

In that atmosphere, 1 kid could have spread it to dozens of kids from different parts of IN easily. 

I had actually delayed entering all of my teams, past the official deadline. We had 20 kids and I had to provide all the info and money for each one of them.

At least it made it easier for him to not have to refund our money  but what a sad ending to the SCI season for all of us, especially the ones running it. 

By pj - May 22, 2020, 10:48 p.m.
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Sounds like you were lucky (no one had cv at your tournament), but also ahead of the curve figuring out how bad it was getting.

By metmike - May 22, 2020, 11:03 p.m.
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The March 7  date of the tournament was set late last year, so we just got super duper lucky.

Our tournament season usually starts in the first  week of November. That first tournament usually attracts over 100 players with almost as many parents there. 

I just can't imagine that there will be any chess tournaments until a vaccine is in widespread distribution or the virus diminishes MUCH more than what is expected.

And it will be very unexpected if this extremely contagious virus doesn't attempt to make a comeback, especially in the fall with the kids back at school.

One of the studies that I read related to the flu virus had suggested humidifying schools in the Winter to increase the humidity in order to shorten the survival  time of flu virus's.

It appears from studies, that doubling the humidity will decrease the amount of flu virus that survives for 1 hour in the air by 50%.

I would think that students at many schools will be wearing masks when they return to school.