Daily update, April 20, 2020....

We begin our 5th week of the COVID-19 shutdown.  I have been following the Virginia Statistics since March 12.  My goal was to understand how the disease was progressing, and to see if we were "flattening" the curve.  (We did).  I used Virginia data because 1) it was reasonably uniform in testing criteria, and 2) I live in Virginia.  I understand the data, which helps.  

Flattening the Curve

My approach was to look at linear trends in the logarithm of the data.  Diseases grow exponentially, and logarithmic plots allow is to understand the growth rate of the disease.  Early in April, I started to see that the number of new cases were consistently falling below the "the trend".  Prior to that, the growth rate day-over-day was about 25%.  And gradually it dropped below the trend line.  

That I did was looked at the data from the 13th to the 30th of March, defined a line, and looked at 2 and four standard deviations.  By about April 5th, it was clear that the multiple days falling below the trend (about 7) was statistically significant, with less than 1% chance (on that day), and essentially zero chance we did not flatten the curve today (April 20).  

Policy and results

Another really interesting aspect of the data is that we can really see the impact of policy changes in the growth rate.  Roughly 7-10 days after a policy change, the number of cases reflect that.  Using the dates of policy changes offset by lag in becoming symptomatic and reporting, we can find each period of time led to a different growth rate.  

Initially, we knew something was up, but did not know it was here.  In that period, we daw a growth rate of 60%.  Fortunately, even though the state of emergency did not go into effect until 3/12, by 3/6, people were aware it was coming.  We were increasing sanitary effect, not shaking hands, using Purell, and washing our hands.  Plus, we were getting weary of crowds.  When the state of emergency was declared, people did not change the actions.  The growth rate dropped to 25%.  With the first executive order, the growth rate dropped to 18%, and with the stay at home order, it dropped to 11%. This is the cumulative number of cases.

This shows that the Governor's decision to take action slowed the spread, and probably saved lives.

Another way to look at this is a what if.  We started to see what was happening elsewhere around 3/4 (Washington State, etc).  Up until that time, we were naive.  We did not have our first case until 3/8.  By then, behavior had changed, but there were other people who had been infected but did not know it.  That put us at 26 cases before we can see the change in behavior.  

We can use this to ask what if's.  In NYC, the first case was about 1-2 weeks earlier.  That would mean for the first 14 days, the we would have not known of the problem, and by that time 2800 would have been infected.  That would probably mean that today, we would have 100x as many cases, and 100x as many deaths in Virginia:  800,000 cases, and 30,000 deaths (instead of 8000 and 300).  Note that we are probably under reporting by a factor of 7 in cases but not deaths.  Thankfully, that did not happen (here), but did happen in New York City.  (Virginia any NYC have about the same population).

Where we are today and tomorrow

These days, we are seeing growth of about 500 cases per day, which is near the maximum, but have not been growing for the last several days.  If we look at the total number of new cases reported in the last 7 days, we see constant values for the last 4 or 5 days.  Projecting forward...it seems that we may be at the peak of the first wave.  Assuming exponential growth rates of two populations in Virginia, 98.7% followed the rules, 1.3% did not, we find that the latter population is saturating.  The 98% of Virginia is still good.  This means we are at the peak of the first wave.  We will know for sure in th coming days if the number of new cases consistently drops.

On the "going forward", if my forecast is correct, we do have a path to reopening the area. It strongly depends on available testing (both active cases and antibodies), sufficient personal protection equipment, and active contact tracing. There will almost certainly be a second wave once we reopen. Our goal is to not overwhelm the hospitals; if we keep the R number under 1.2, we can succeed. That coupled with better treatments (some -- not those advocated by our so-called leaders are showing promise in the most severe cases), we can survive this (or most of us can).

If we reopen today, with where we are, this shutdown was for nothing.

My NFL Playoff Predictions: NFC

The regular season is over...we know who will be play whom. So, I will give my thoughts on the playoffs and why.  I will stat with next week's games in the NFC.

First Round:

Detroit at New Orleans....In my opinion, New Orleans is playing the best football in the league right now.  Detroit, not so much.  I go with New Orleans.  Frankly, I expect the Saints to win it all.

Atlanta at NY....This is tougher.  It depends on which Giants team shows up.  Is it the team that lost to the Redskins twice, or the team that swept the Cowboys?  Good Giants, and this could be a good game...but my edge goes to Atlanta.  Nothing more, nothing less.


Divisional:
New Orleans (projected) at San Francisco.  This will be an interesting game.  San Francisco is easily the biggest surprise of the year.  And I like the way they play: tough.  The defense will have to stop the Saints offense, and that is where the battle will be:  Niners e defense vs.  Saints offense.  The Niners have a good running game, and I do not think the Saints have a defense.  If this was a field position game, I would give the edge to the Niners, with the best punter in the league.  But it will not be that type of game.  I would love to be wrong, as I love the grit of the Niner's, but I have to go with the Saints.

Now, if Detroit manages to upset the Saints in round one, then I pick the Niners.  And I think Harbaugh will take Schwartz in the post-game UFC fight to the death match.

Atlanta at Green Bay.  Conventional wisdom says the Green Bay Packers, a one loss team, will win big.  But, Green Bay does not have a defense.  The defense is based on turnovers.  The offense is good.  Very good.  Atlanta is a good all around team.  Atlanta has a good running game.  The real question in the game is how will Green Bay play in the cold weather.  With there offense we able to play, or will there be a lot of dropped balls?  I want Green Bay to win, because I would love to see Saints vs Green Bay, but I am unsure of the pass happy offense in Green Bay in the cold.  Atlanta in a low scoring game.

Championship:
Atlanta at New Orleans:  This could be interesting.  The teams know each other.  They do not like each other.  New Orleans swept Atlanta.  New Orleans ran up the score.  Atlanta will come in angry.  Look for fights.  Look for personal fouls.  And look for New Orleans to win and win big.

If Green Bay beats Atlanta, I am going to have my popcorn and watch a high scoring game, except for the cold in Green Bay.  Can Brees play in the cold?  He did at Perdue.

So, from the NFC, I am expecting New Orleans to go to Indianapolis.

Reflection on Sumatra: a scientists perspective

Seven years ago, Dec. 26, 2004, was a really bad day for people in the coastal regions of the Indian Ocean.  The Magnitude 9.1-9.2 Northern Sumatra-Andaman Islands Earthquake triggered a tsunami that traveled across the globe, and killed more than 230,000 people, most without any warning.

It was an exciting, yet humbling day for seismologists.  For the first time, we captured a true megathrust earthquake with modern instruments.  We were humbled when our processing algorithms failed because we did not think an earthquake could last 10 minutes; most magnitude estimate algorithms assumed earthquake ruptures of about 200 seconds or less.  So, the initial size estimates were low:  8.0 - 8.5.  About six hours later, modifications had been made to allow for the long duration, and the magnitude was estimated to be about 9.0 (and was revised up to 9.2 based on analysis of the earth's free oscillations).

But, that was not why there was no warning.  The reason there was no warning was that there was no Indian Ocean tsunami warning system (today there are multiple warning systems in the Indian Ocean).  Before the earthquake even finished rupturing, the scientists at the Pacific Tsunami Warning Center had realized that the earthquake was big.  However, they are the Pacific Tsunami Warning Center, not the global tsunami warning center.  The PTWC initially sent out a message saying that the earthquake was outside of the Basin, so no threat (in the Pacific) was anticipated.  About one hour later, they revised the message, increasing the magnitude, and indicating that:

 REVISED MAGNITUDE BASED ON ANALYSIS OF MANTLE WAVES.
 THIS EARTHQUAKE IS LOCATED OUTSIDE THE PACIFIC. NO DESTRUCTIVE      
 TSUNAMI THREAT EXISTS FOR THE PACIFIC BASIN BASED ON HISTORICAL 
 EARTHQUAKE AND TSUNAMI DATA. 

 THERE IS THE POSSIBILITY OF A TSUNAMI NEAR THE EPICENTER.  

This was prior to the tsunami arriving at Thailand, Sri Lanka, India, etc.  However, there was no mechanism to distribute the warning to the people that needed the warning.  The PTWC  can issue a warning, but it is up to the countries to issue the warnings to their citizens.  And there was no mechanism to get the message to Sri Lanka, India, etc.  Thailand actually received the warning, but they did not have a means to disseminate the warning on the Indian Ocean coast.  As the scope of the disaster began to unfold, with reports of damaging waves in Thailand and Sri Lanka, the warning center personnel tried to stay ahead, attempting to create an ad hoc warning system.  They were able to provide warning to the African coastline.  Thus, the only country in Africa with significant loss of life was Somolia, which was in a state of anarchy.

We learned a lot about earthquake processes in the ensuing days.  First, we discovered that earthquakes can rupture 1000 km or more.  Second, we confirmed that, just because the earthquake has not been recorded, does not mean it is not possible (a lesson repeated in Japan, 2011).  We learned that it is possible to have a tsunami propagate from one ocean to another:  the tsunami was observed in the Indian, Atlantic and Pacific Oceans.  For the first time, we had deep water measurements of a damaging tsunami -- based on satellite data.  And, we recorded the energy on scale on seismometers, acoustic sensors, GPS receivers, tide gauges, etc.

As an example, using a hydroacoustic (sound in the water) station at Diego Garcia deployed for the Comprehensive Nuclear Test Ban Treaty Organization (http://www.ctbto.org), we were able to image the rupture.  Independently, four groups did similar analysis.  A movie I made based on my analysis is shown below:

Back projection of energy from Diego Garcia.  Note that when the energy is larger, the incident direction maps out the aftershock zone.

As a scientist, my role is to learn from events such as this.  Nothing I do can bring back the 230,000 people lost on December 26.  However, our collective increase in knowledge can help save lives for future events.  The March 11, 2011 Tohoku earthquake produced a tsunami that would have killed people in the far field had there been no warning.  In the end, outside of Japan, only one person drowned, and he drowned because he went out on a jetty to photograph the tsunami.  

Too many bowl games!

I am watching the MAACO Bowl.  Boise State -- a very good football team, probably should be playing in January against an undisciplined Arizona State.  Yesterday, I watched TCU play La Tech in the Poinsettia Bowl.  Better yet, on Tuesday, I watched Marshall and Florida International play in the Beef O'Brady Bowl.  I have no idea what Beef O'Brady is -- it seems to be a chain of sports bar's / pubs, according to their website (http://www.beefobradys.com/Default.aspx).

Do we need a Beef O'Brady Bowl?  I guess if it is making money, it is ok.  But there are 32 bowls.  I think every team that won 6 or more games against Division I teams is in a bowl.  Why?  I am watching the bowls played to a lot of empty seats.

After today, I think I will watch only a few bowls.  I will watch the championship game, and I watch the Sugar Bowl.  Sugar Bowl because I am a Hokie Graduate.  I was shocked when we got the bid, I did not think we deserved it, but we did and I will watch it.


And I may watch Saturday's American Standard Toilet Bowl at Redskin Stadium, but that is an NFL game featuring two bad teams: the 2-12 Vikings and the 5-9 Redskins.

Some thoughts on the rates of Big Earthquakes

I am an earthquake seismologist by training.  When people here that, I get to questions:  1) Can we predict  earthquakes (I do not think so), and 2) are the rate of big earthquakes increasing.  I am going to discuss the latter here.

If we look over the last 40 years, the rate of big earthquakes has increased.  From 1971 to Dec 25, 2004, there were no magnitude > 8.5 earthquakes, whereas since then, there have been 5.  However, this is an example of statistics of small numbers.   In the 10 years from 1952 to 1965, there were 7 earthquakes above 8.5.    Before that time, we may not have had the ability to measure the truly big earthquakes.

Here is a picture of the rate of earthquakes above 8.5:

But, again, this in only showing 15 earthquakes.  And not all earthquakes above magnitude 8.5 are created equal.  If we look at the total seismic moment of all earthquakes recorded, which is probably proportional to the energy, we see that 1/2 of the moment since 1900 occurred between 1952 and 1965, and about 1/4 - 1/3 occurred in one earthquake:  the May, 1960 Chile Earthquake (Mw=9.5)

from: http://www.iris.edu/news/events/japan2011/images/ModifiedPAGERCumMoment-ShallowEQ-Apr2011.png

This shows that the background rate of earthquake slip is relatively similar, except it is dominated by slip from the truly great earthquakes: 1952 Kamchatka, 1960 Chile, 1964 Alaska, 2004 Sumatra, and the recent Tohoku (Japan) earthquake.  All of these events were above magnitude 9.0.   

As an example, the following video, produced by Dr. Nathan Becker of the Pacific Tsunami Warning Center, shows the relative size of various earthquakes.  I think this is one of the best visualizations I have seen.

What this showed us is that these biggest earthquakes are responsible for most of the energy release.  And there are few enough of these instrumentally recorded that we can not make any conclusion regarding the long term rate of earthquakes. 

Here is a link to Dr Nathan Becker's discussion of earthquake magnitudes:

https://sites.google.com/site/nathancbecker/presentations/earthquake-size-and-frequency-part-3

Scientific Data is not political!

I read a troubling article in The Washington Post (link: http://www.washingtonpost.com/national/health-science/virginia-residents-oppose-preparations-for-climate-related-sea-level-rise/2011/12/05/gIQAVRw40O_story.html?tid=pm_pop)  about communities near the Chesapeake Bay in Virginia that think that sea level rise and global warming are political issues and not scientific issues.   Apparently, elements in the community do not want the land planning groups to consider the impact of sea level rise on zoning.  Some citizens equate sea level rise with global warming, and since they do not believe that human activity is increasing the global temperature.  However, these community activists are simply ignoring sea level data.

According to data based on ocean height measurements from satellites, as reported at http://sealevel.colorado.edu/, consensus is that sea level is rising at 2.6 to 3.5 mm/yr.  In other words, since, 1992, sea level has risen about ½ meter.

(http://sealevel.colorado.edu/files/2011_rel4/sl_ns_global.png).

This is data, not politics.  Ignoring the impact of sea level rise will increase risk to storms and other ocean based disasters.

Racism and Anti-Semitism in the South, 1975 An 11 year old’s experience moving from NYC to Western-Most Florida

For the first eleven years of my life, I lived in places where my Judaism was not an issue, as we had lived in the suburbs of Washington, DC and New York City.  In 1975, that all changed with a family move to the Panhandle of Florida.  My family moved to Gulf Breeze, Florida, which is a “suburb” of Pensacola.  We moved to Florida because my father joined the Navy, and was to be trained for  approximately 5 months.  My parents went ahead to find a place to live;  the number-one concern was finding a place with safe an good public schools.  For that, they were directed to the town of Gulf Breeze.  My parents found a waterfront townhouse in Gulf Breeze that was available for a short-term rental.

We moved to Gulf Breeze in August, 1975, about three days before the school orientation at Gulf Breeze Middle School.  At Orientation, what struck me first was that everyone was White.  There were no Blacks, Asians, or Hispanics. 

Back then, on that hot August day in 1975 at Middle School Orientation, for the first time in my life, I felt out of place…different.  Why?  The Principal of the school started orientation with a prayer to Jesus for a good year.  I had never been asked to pray to Jesus before.  And I didn’t.  My mom was furious and wanted to make a big deal. I just wanted to fit in.

The first few weeks were fine.  We went to the beach a lot, and I tried to make friends.  Rosh Hashanah was on a weekend…but Yom Kippur was on a Monday.  That meant that I had to miss school.  When asked about the absence by my classmates, I explained that it was a religious holiday for me:  the holiest day of the year.  In hindsight, I should have lied and said I was sick.  Because after that, things started to change. 

I do not remember the date that things went to outwardly hostile, but I remember that it was between Yom Kippur, which was September 15^th, and before Hurricane Eloise, which was Sept 23.  During that week, I was out on the pier with my sister.  One of the neighborhood boys and his “gang” were making racist comments about black people – how they smelled funny.  My sister commented back, something like, “Have you ever been close enough to smell one, because one of my best friends was black, and she did not smell bad”.  At that point, the leader, who was a few years older than I, called my sister a “Nigger Loving Pollack Jew”.  My sister corrected him:  We are only half Polish (or is it Austrian?  Borders change). 

At this point, the leader started his dirt bike, and chased me down to the end of the pier.  His friends then threw me off of the pier, saying that the dirty Jew needed to be cleaned.  I swam to shore, at which point they carried me back out to the end of the pier and threw me off again.  And again, and again.  I think it repeated at least one dozen times.   

The next day, in school, his friends beat me up.  We all got sent to the principal’s office for fighting  One of the boys went as far as saying I started it for being Jewish.  I was the only child punished. In 1975 in Gulf Breeze, Florida, being Jewish justified corporal punishment.  The other boys continued beating me without punishment.

At home,  I gave up riding my bike: every time I was out the bike, the leader would try to run me off the road with his dirt bike.  I would only go outside when no one was around; otherwise I would get beat up.  But I could not avoid them in school.

Somewhere during this time, a cross was burned in front of the school, because of the loss of purity, and there was a bomb threat against the school…It seemed to me that the principal of the school blamed me, as I was the difference that was causing the problems….without me, everything would have been fine.  So, the paddling continued.

 I remember one day, probably in mid-October, where at lunch or recess, I was playing on the monkey bars.  I was pushed from about six feet up, not by accident, but because of what I was. I landed hard in the sand, head first.  I had a seizure from the blow.  When I woke up, the other kids were kicking sand on me, saying how they will bury the Jew.  Hopefully, today, the injury would be recognized as serious.  Then, they would have sent me back to class, except I wet myself while passed out.

That was the last time I went out during recess.  The only person who seemed to understand was my art teacher.  She invited me to come into the  art room for the free time.  Between classes, though, the beatings continued.   And, reports of me fighting, followed by the paddlings.  One day, the principal told me the best thing to would be to accept Jesus.   Then, everything would be fine. 

The good news was  that my Father’s assignment was temporary.  I think he graduated from Flight Surgeon school on 18 Dec 1975.  By Thanksgiving, we knew my father was being assigned to Naval Air Station Lemoore in California. Around my birthday, my parents informed the school that we were moving in a few weeks.  My mom then pulled me out of school for the remainder of our stay.

Thirty-six years later, I think I understand the impact this experience had on my life.  Through my teens, 20’s and even 30’s, when encountering perceived injustice, including anti-Semitism, my reactions were much stronger than the situation warranted.  I think I have since mellowed.  Such reactions have resulted in a wedge between me and other people.

My experiences have also shaped my political views.  I am moderate overall, but believe in an absolute separation of church and state.  Any politician that tries to blur that line will not get my support.  That, more than anything, is why I am a Democrat.

I  am incredibly proud of what I see in the current crop of youngsters in Northern Virginia.  Mty daughter and her classmates not care about the differences in outward appearances.  They are all just children, playing.  Black, White, Hispanic, Indian, Korean, Chinese, Arabs, etc: the kids see a playmate.  The children today make me proud and hopeful for the future.

I have heard that since the mid 70’s the south has changed.  However, according the the Gulf Breeze Middle school web site, the school remains largely white (88%), with only 0.47% African American students. 

David Salzberg

December 17, 2011

36 Years to the day from when we left Pensacola.

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