Police Justice, Climate Justice and Hurricane Laura - The perfect storm

 

Caption:  Hurricane Laura on Wednesday Evening, August 26, 2020

It feels like the movie called "The Perfect Storm" because many things are happening at once: Hurricane Laura,  COVID-19, the opening of universities, the RNC after the DNC, and finally the vicious shooting of Jacob Blake.  I don't know how any sane person can stay focused on anything like work or even writing a blog.  I just pray that God and the ancestors will not allow this situation to persist and will protect the innocent because the police don't seem to be able to deal with that responsibility.

Since Hurricane Mitch and Georges back in the day, every time I see an eye like the one associated with Hurricane Laura  I feel fear for the people on the ground.  This fear has only increased since Katrina but new named Storms come to the surface of my mind, like Matthew, Michael, Dorian, Maria, Harvey, and Irma.  While I know that we can't control a hurricane, but we may be influencing it through the burning of fossil fuels leading to warmer ocean temperatures --the fuel of hurricanes.  For people of color, this is another series of threats that many have faced their entire lifetime from systemic racism, harassment, job security, educational access, and police violence.  

This storm is different, because of COVID-19.  Many have mentally and emotionally struggled over the last 6 months, but with this impending storm, a new struggle emerges.  Shelters must take in fewer people because of COVID-19 while power, transportation, and communication will be impacted and the money required to recover will be hard to come by for many because so many people are not working.  Will the government help and not play politics?  Nature through the Coronavirus, a warming Climate and now Hurricane Laura is trying to get our attention.  

Uncertainty about the impacts of climate change, Hurricane Laura, COVID-19, and the police violence toward black people make for "the Perfect Storm"  on August 26, 2020-- what I fear is that a new  "Perfect Storm" sits on tomorrow's horizon for us, our children, grandchildren, and great-grandchildren.  

Disturbance moves quickly and weakens... lowering threat of flooding and strong winds on Cabo Verde

 

Caption:  2000 UTC EUMETSAT Infrared images 

This evening things are looking up.  The disturbance moved very fast towards Cabo Verde with no time to develop further.   The convective clouds are warmer and lack structure with the low-level center.  The WRF model weakened the storm between 0000 and 1200 UTC and moved the rainfall northward. 

The 1200 UTC WRF forecast shows limited convection and weak center of low pressure and weak surface winds for the next 36 hours.  

Caption- WRF hourly Sea Level pressure for 21 August 1200 UTC - 23 August 0000 UTC

Caption- WRF hourly Maximum dbz for 21 August 1200 UTC - 23 August 0000 UTC

Caption- WRF hourly Surface winds (knots )for 21 August 1200 UTC - 23 August 0000 UTC

Summary 

There should be some rain over the country during the next 36 hours but should not be anything to cause disruptions.  However, continue to tune in to local weather station just in case situation changes but for now.... CV is good to go.

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Cabo Verde to Experience Strong winds and heavy rain in next 24 hours

Last night I was uncertain about the model forecasts but this morning I feel confident that Cabo Verde will experience heavy rain over the next 24 hours (https://distilleryafrdiaspora.blogspot.com/2020/08/data-void-west-africa-makes-tropical.html). The question is how much will this system develop before impacting the country.  

It is moving fairly fast and so may pass over quickly.  The forecast model guidance is not so clear about this but yesterday's 12 Z model run had the center of the disturbance passing very close to Praia.  Yesterday's forecast suggested a center would form off the coast of Senegal and it did.    This forecast shows that area of low pressure and surface winds in the 30-35 knot (55-65 kph) range will pass near Praia tomorrow morning.  

Caption:  WRF forecasted surface winds in knots 

The 8 AM advisory states that strong winds and heavy rain are likely.  

The WRF forecast from yesterday suggests rain will be heaviest in the southern portions of Cabo Verde.

Caption:  WRF forecasted maximum reflectivity, sea level pressure, and wind vectors  

Caption: 72-hour rainfall in mm for Cabo Verde.

However, this model always underestimates rainfall so this is just guidance.  

Thoughts 

If you live in the southern Islands of Cabo Verde including Brava, Fogo, and Santiago (including the capital, Praia):

1. be very careful on the roads over the next 24 hours for flooding. 

2. secure any items that strong winds might blow over

3.  Pay attention to your local TV about changing conditions or messages from Civil authorities.

I will post new forecasts over the next few hours.

 

Data Void West Africa makes Tropical Cyclone Forecast for Cape Verde very Challenging

     Caption:  EUMUTSAT IR image of convection on Thursday 2000 EDT, 0000 UTC Friday

This evening a strong area of convection is found to the South of the Cabo Verde Islands and to the west of Senegal. This would make you think that there is no possibility of Cabo Verde being threatened by this storm right???  Wrong.   The GFS and WRF forecast shows that it is the area to the NE of the convective center that may develop into a strong tropical low. 

Unfortunately, the other global models (ECMWF and Candian models) show a very weak disturbance and not a clear indication that anything will happen this weekend.  So what is the big deal???

DATA...DATA..... or LACK OF DATA in Africa

Well, weather forecast models need good initial conditions in order to have a good forecast.   Well, that is just the real trick.  The atmosphere is three dimensional (x,y,z) and needs information about the initial state for models to have some degree of accuracy.  So every day, all around the world balloons are launched called radiosondes which provide information about the state of the atmosphere.

            Caption:  Radiosondes to provide information about the state of the atmosphere

The data from these balloons are fed into computer models all around the world and help them to produce accurate forecasts.  This is especially needed for severe weather such as tornadoes, severe thunderstorms, and hurricanes.  In fact, for hurricanes, the airforce and NOAA might fly inside of the hurricane use dropsondes which have parachutes rather than balloons to get a sense of what the atmospheric conditions inside of a hurricane.

However, in  West Africa, we do not have twice per day launches that occur to help models determine the state of the atmosphere. On a typical day, like today there are no measurements for potentially thousands of miles.  And most stations will only launch a balloon once per day.

    Caption:  Reported radiosonde launches for 20 August 2020.

This means that there is a poor representation of the state of the atmosphere at the time of the forecast.  Well, so what?  It means that if a tropical depression, storm or hurricane is forming off the coast of Africa the initial conditions could be poor leading to a poor forecast for coastal West Africa and Cabo Verde.  

At any rate, throughout the day the WRF model has provided some guidance about this weekend.   This is the WRF forecast from 0600 UTC 20 August.  

Caption:  WRF forecasted sea level pressure, wind and max reflectivity

If the WRF and GFS forecast are correct, then Friday, August 21 we will see the formation of an area of low pressure off the coast of Senegal.  This low will move to the NW and impact Cabo Verde starting Saturday night through Sunday.

If nothing happens, it gives a sense that we still have a long way to go in the forecasting realm.

Let's hope that that the weather system off the coast does not impact Cabo Verde in a big way.

 

 

African Easterly Waves are in full Effect. Make sure that you are prepared for the heart of the Hurricane Season

This year has been an extremely active tropical cyclone season for the Atlantic Basin.  The next named storm is Laura.  In comparison, Hurricane Katrina occurred during the last week in August, which was the record season for the numbers of named storms.   Each year I watch for the source of Cahurricanes -- The African Easterly Waves (AEWs) in mid-August.    In the tropics, we don't see large sea level pressure changes at the surface so we need to examine the atmosphere at 5000-10000 feet above the ground and depend on models and satellites.  The number of actual measurements has fallen to only a handful across much of Africa north of the Equator in recent years.  This leads to errors in the forecasts but data assimilation and ensembles of forecasts can help to reduce the error.   Still this is a major concern for the people in West Africa.

Typically, between August 15-25 these waves become strong and Saharan air and dust events into a quiet mode.  Dusty and warm Saharan air limit AEWs from developing into tropical cyclones because the air is (1)  bone dry; (2) super stable; (3) has high shear which does not allow clusters of thunderstorms to last very long.  Another ingredient is warm water, which increases to values above 80F by late August.  So from a climatology point of view, the peak of the season occurs during the second week in September (Figure 1).

Figure 1:  Frequency of Hurricanes (Source NHC)

So what's up for this year.   Well first of all the monsoon has been very strong leading to above normal rainfall for much of West Africa for the last 3 months (Figure 2) and also the last month (Figure 3). 

Figure 2:  Satellite-based percent normal rainfall over the last 90 days (Source NOAA).

Figure 3:  Satellite-based percent normal rainfall over the last 30 days (Source NOAA).

The above-normal rainfall is partly due to the AEWs and also fast-moving squall lines which can dump lots of rain in a short period of time.  The African Easterly Jet (AEJ) -an zone of fast winds, which is also located at about 10000 feet has shifted further north.   Like the North American Jet in the winter season, we find AEWs developing just south of the AEJ.  This year the AEJ has been very far north, over the desert like the rainy period of the 1960s.  Consequently, I would expect strong AEWs and heavy rain over the Sahel region of West Africa during the next 4-6 weeks.  

AEWs over the last week

Three systems over the Atlantic are tied to AEWs that emerged off of Africa in the last week.  Two of them have the possibility of forming named storms in the next 5 days.   The last system which emerged off the coast of Africa on Saturday is in struggle mode but still might form a TC.

https://www.washingtonpost.com/weather/2020/08/17/atlantic-hurricane-activity/

I typically run the Weather and Research Forecasting model to get a sense of the wave.  I examine 850 hPa (4500-500 feet) and 700 hPa (10000 feet) Vorticity which gives us a sense of spin and where AEWs are located.   For the strongest AEWs the vorticity centers at 850 and 700 hPa are co-located and closed but normally you don't find a close circulation at 700 hPa.  The AEW normally looks like an inverted V pattern at 700 hPa.

Figure 4:  850hPa Vorticity field with red showing counter-clockwise or cyclonic motion for 17 August 2020

Caption:  700hPa Vorticity field with red showing counter-clockwise or cyclonic motion for 17 August 2020

AEWs over the next two weeks

AEWs have been moving across West Africa every 3-4 days on a regular basis bringing plentiful rain to farmers and sometimes flooding.   However, the long-term forecast suggests that there will be a tendency for the waves to form near the coast of West Africa in addition to traveling over land.  We can see this by tracing north-south winds over time in the model forecast.  Alternating series of negative and positive meridional (north-south) winds that move on the diagonal can be identified as AEWs (Figure 4).  They show the waves moving from east to west (just follow a blue area and look at the date)

Figure 4:  Time series of meridional winds (negative - from north, positive from South) at 700 hPa.

If we roll the 850 vorticity into a movie you can get a sense of the waves moving across West Africa and also developing off the coast of West Africa (Video 1).

Video 1:  2-week (August 15-29 2020) forecast of 850 hPa Vorticity movie

The AEWs also will carry precipitation with them as they move westward which is underestimated in the forecast (Video 2).

Video 2:  2-week (August 15-29 2020) forecast of 850 hPa Vorticity movie with forecasted 

radar reflectivity

The African Easterly Jet (AEJ) northward location over the Saharan Desert during the next two weeks, will create new disturbances and assist in generating spin as they move across the Atlantic ocean towards the Caribbean and Western Atlantic (Video 3). Again, we know that when the AEJ is this far north, AEWs and tropical cyclones are typically stronger.

Video 3:  2 week (August 15-29 2020) forecast of 700 hPa winds (AEJ)

Be prepared over the next 8 Weeks 

We don't know where potential hurricanes will land, but you must be ready if you live in the Caribbean, along the Gulf of Mexico or Eastern US seaboard and Cabo Verde as this may be a record hurricane season in terms of numbers of storms.  Some of these hurricanes may become major hurricanes.   There is no reason why you can make sure that you have:  (1) non-perishable foods and some stored water; (2) extra cash in the event of a major power outage; (3) have all of your important documents in a safe place that you can grab on a minutes notice; (4) Make sure that prescription drugs are filled for yourself or loved ones and have a contact list; (5) have an evacuation plan and know where shelters are located.  

This year COVID-19 is going to make going to shelters particularly challenging.  So you have to make a very important decision if the time should come:  Which one is more likely to injure or kill me in the short-run (Hurricane or COVID-19)?  This is not an easy decision if you have co-morbidities such as diabetes, cardiovascular disease, or kidney disease.  But you must make the decision not based on fear but on reality at the moment.   If you have to go into a shelter, make sure that you have some extra masks and hand sanitizer to keep you and love ones safe.  

Note:  If movies do not work, I am sorry.  In the process of building a website.  Stay tuned..

 

COVID19 makes its presence known in SubSaharan Africa... Will South Africa become the next Brazil

About 1 month ago, I posted about COVID in Africa and potential links to the environment.  At that time the numbers were as follows (based on WHO and Worldometer):
 
June 11                          Cases                Deaths              Total Case fatality (%)
Cape Verde  -                  657                   6                       0.9
Nigeria                            14,554              387                   2.7
Senegal                            4,759               59                     1.2
Ghana                              10,358              48                     0.46       
Angola                             118                   5                       4.24
DRC                                 4,515               98                     2.17
South Africa                     58,568             1284                 2.2

South Africa had by far the most COVID-19 cases and deaths and Angola the least.  The total case fatality represents the fraction of people who died after testing positive.    South Africa, Nigeria, and DRC all had case fatalities that were significant.

Since that time, the dry season is now in full swing south of the Equator and north of the Equator, the wet season is occurring.  The dry season is associated with biomass burning in places like Angola, Zambia, Madagascar.

Satellite depiction of Fires South of the Equator (July 14, 2020)

The fires produce poor air quality and lots of small aerosols made up of black carbon.  Very bad for the lungs overall and especially during the COVID-19 Pandemic.

Satellite depiction of clouds and rainfall north of  the Equator (July 14, 2020)

In West Africa, the commencement of the rainy season is tied to cool and humid conditions, rain coming from organized and disorganized weather systems.  Over the next three months, some of the weather systems will move westward and become tropical depressions, storms, or hurricanes impacting the Caribbean, Central Americas, and the United States.    The rainy conditions over West Africa are linked to vector-borne and water-borne diseases such as Malaria, Yellow Fever, and Cholera.   Also, the flu becomes prevalent in West Africa during this time which combined with COVID-19 could be very impactful.


Current status of Covid-19 in Sub-Saharan Africa

July 13                            Cases                Deaths              Total Case fatality (%)
Cape Verde  -                  1698                   19                    1.1
Nigeria                            32,558              740                    2.27
Senegal                            8,198               150                    1.83
Ghana                              24,518              139                   0.57
Angola                             506                   26                     5.14
DRC                                 8075               190                    2.35
South Africa                     276,242          4079                  1.48   

In the last 30 days, the numbers of cases have by a factor of 2-3 in most cases but somewhat higher in Angola.


July 12 single day          Cases                Deaths              
Cape Verde  -                  75 (july13)                                   
Nigeria                            571                    16                 
Senegal                           121                                   
Ghana                              270                                 
Angola                             21                                     
DRC                                 62                                   
South Africa                     12,058             111               


Let's take a look at North and South of the Equator as this may provide some clues as to the role of the environment.

South of the Equator (Angola, Botswana South Africa)

Caption: New and cumulative COVID-19 cases in Angola, Botswana and South Africa

Angola and Botswana have less than 1000 cases each.  However, you would note that the majority of the cases have occurred since June 1st and are rising.  This was the start of the biomass burning season where pollution levels have increased.

South Africa, on the other hand, has demonstrated exponential growth with the number of COVID cases approaching 300,000 today and new cases between 10,000-14,000 per day over the last week.
South Africa is now #9 globally, with only the United States, Brazil, and India recording more cases per day.  Based on the current growth, it will be in the top 5 for COVID-19 cases before August 1st.

Caption: Cumulative Mortality in South Africa and Botswana

As for fatalities, South Africa is also showing an exponential growth curve with most of the deaths occurring since June 1.  Botswana, on the other hand, has recorded only one fatality since May.




North of the Equator (Gulf of Guinea) 

Caption: New and cumulative COVID-19 Cases in Nigeria and Ghana

Nigeria and Ghana are major economic forces in West Africa and both have experienced increased in COVID-19 Cases since late May.  This coincides with the start of the rainy season which I will discuss in the next blog.  Since June both countries have experienced 400-700 new cases per day.

North of the Equator (Sahel and Cabo Verde) 

Across the Sahel (Senegal, Mali, Burkina Faso, Niger), the number of cases has been considerably lower up to the present.  These countries have yet to experience the full monsoon but the rainy season has gotten off to a fast start.   Cabo Verde has the same rainy season as Senegal and so we also compare values there.  Cabo Verde has more recorded cases than Niger and Burkina Faso whose populations are 20 times larger.   I don't know if it is because there are fewer tests in these countries or if the virus is moving quickly in Cabo Verde.  It does seem a bit odd.

Caption:  New and Cumulative  COVID cases in Senegal (left) and Cabo Verde 

Both countries show that COVID-19 cases continue to rise since May.  Senegal and Cabo Verde are averaging more than 100 and 40 cases per day since June 1.  Senegal has more than 8000 cases and Cabo Verde more than 1600.   Because Cabo Verde has only 550,000 persons and Senegal 16 million there are more cases per person in Cabo Verde.



COVID Mortality north of the Equator 

Covid Mortality in Nigeria/Ghana (Right) and Senegal/Cabo Verde (left)

COVID-19 mortality has increased in Nigeria and Ghana, but Nigeria has 5 times the number of COVID-19 deaths.  More than 400 COVID-19 related deaths occurred since June 1 in Nigeria.  It would be interesting to know what other co-morbidities (hypertension, asthma, flu, cardiovascular disease).  

COVID-19 Mortality in Senegal is similar to Ghana with rapid increases since June 1.  Cabo Verde has seen a rise in deaths since June 1st.  What co-morbidities are driving fatalities in these countries?

Is South Africa the next Brazil?

South Africa and Brazil are two good examples of emerging economies that have a significant number of black people. Brazil is about 4 times as large (200 million people) as South Africa (55 million).  The rapid rise in COVID-19 cases in South Africa is alarming.  However, there are 3-5 times more cases per day reported in Brazil.

Caption:  New and cumulative cases in Brazil (Left) and Brazil and South Africa Mortality curves.

Part of the problem in Brazil has been the same as the United States, the failure of leadership to acknowledge COVID-19 as a public health threat.  I believe that the South African government does not take such a position, but Brazil should be enough warning for all of Africa to take heed and as my brother, Jeff says to govern themselves accordingly.

Looking at the cumulative death curves shows that South Africa is about 3-6 weeks lagging Brazil. South Africa is in the heart of its winter season where several factors such as pollution, and colder temperatures (40s and 50s) keep people indoor.  Near Cape Town, large winter storms will be rolling by every week bringing rain, wind and cooler temperatures. This is their flu season and a prelude to what is expected in the United States in 4 months. 

In the next blog, I will give an overview of observed Environmental conditions in north and south of the Equator and how they may have influenced COVID-19 over the last 1-2 months.

Could there be a lower number of fatalities in Africa relative to Europe and the United States?? 

Some have stated that because the populations of Africa are so young relative to other countries, that more people will survive COVID-19.  This could be the case as we see in the US that a larger number of younger people have come down with COVID-19 and the current death rates are lower.

However, you have to be extremely cautious with this perspective.   For example, we know that the access to medical care is poor in many regions of the continent. We know that non-communicable diseases like asthma, diabetes, hypertension, and cardiovascular disease are emerging across much of Africa.  We also know that people have fewer resources and disposable incomes to deal with COVID-19 related illnesses.   Finally, the number of tests outside of South Africa remains low in SubSaharan Africa, so that there could, in fact, be many more cases than reported.  No matter, I urge black people in Africa and the diaspora (Caribbean, Europe, US, South America) to remain vigilant to COVID-19, because..... Black Lives Matter everywhere.

Is a COVID-19 spike on the way for Africa-??- The possible role of the environment

A few weeks ago, I was interviewed about COVID-19 in West Africa with a focus on the upcoming rainy season.

https://voicesfromthefrontlines.com/2020/05/27/voices-radio-this-week-we-are-joined-by-gregory-jenkins-professor-of-meteorology-atmospheric-science-geography-and-african-studies-at-penn-state-about-climate-change-and-covid-19-in-africa-then/

COVID-19 has ravaged most of the world, with the largest number of cases in the United States. South America and Brazil in particular has become the Epicenter of COVID-19 and  India is now becoming a new epicenter and at #4 for the total number of cases behind the US, Brazil, and  Russia.
In the United States, the black community has suffered the burden of COVID-19 mortality, and confounding issues related to hypertension, obesity, diabetes and cardiovascular disease have played a role in mortality.

What is the role of the environment in the increase of COVID-19 and COVID-19 mortality?  Over the past two months, a number of articles and presentations have examined the roles of seasonality and air pollution on COVID-19 in China, Europe, and the United States.  Those results have pointed to pollution as a potential factor in COVID-19 mortality.  Particulate matter and NO2 which is a pollutant often found in urban areas where automobile traffic this short-lived pollutant.  However, particulate matter, especially PM2.5 has also been linked to COVID-19 deaths. a study under review shows that an increase of 1 microgram/meter cubed of particulate matter leads to an eight percent increase in COVID-19 mortality.  Furthermore, earlier studies show the highest mortality in African Americans over 65 due to air pollution; African Americans also live near sites where the burden of pollution is much higher than for whites.  Some of this is definitely tied to historical and environmental racism in the United States.

https://www.nationalacademies.org/event/05-28-2020/basc-session-on-air-quality-climate-variability-and-covid-19

SubSaharan Africa has experienced the smallest number of cases relative to the rest of the globe.   But is this about the change???? 

There are several reasons to be worried:

1.  The hospital infrastructure in much of Africa is much weaker than the US;
2.  Coastal West and Southern Africans share the same DNA pool as the African Americans and Afro-Brazilians with likely similar risk factors leading to COVID-19 mortality;
3.  Many of the noncommunicable diseases such as diabetes, stroke and cardiovascular disease have emerged to outpace to infectious disease in some cases;
4.  Biomass burning and dust pollutes many thousands of square kilometers and exposes tens of millions of people of short periods of time (days);
5.  Megacities in Africa have exploded with too many cars and pollution levels are likely to be high;
6. The wet season, which is similar to the winter season in the United States is likely to lead to influenza which may increases susceptibility to serious health outcomes from COVID-19;
7. Vector-borne and water-borne diseases will arrive with the wet season with has begun in countries like Nigeria and will begin starting in July further north in Sahelian countries;
8.  Many governments have allowed businesses, schools and universities to open;
9.  There is no vaccine.


I am going to focus on what we know about the changes in COVID cases and the Environment (my zone).

How Seasons in Africa Work

Rainfall patterns in Africa (mm/month for winter, spring, summer and Autumn )

The rainfall in Africa (25N-25S)  tends to follow the overhead Sun  leading to the following pattern if you are in West Africa and North of the Equator:
Wet Seasons (May-October), Dry Season-fire (November-April) in West Africa 

If your location is in Nigeria, Ghana, Togo, Benin, you are likely to get rain in March which moves north with a short drier period in August followed by a second wet period.    If you live further north in Senegal, Mali, Niger you get one rainy starting in July and ending in late September.  The entire region will become dry by December in general.  During the dry season, there is the Harmattan with dust from the Sahara desert and lots of fires linked biomass burning.



If you lived south of the Equator in Southern Africa
Wet Seasons (November-April) Dry Season-fire  (May-October), in Southern Africa

If your life in the Republic of Congo, Angola, and Zambia the rainy period begins in November through April.  The rainfall patterns in the Southern Hemisphere are varied and as one goes further eastward the pattern becomes more complex. Beginning in May we see large scale fires in Southern Africa linked to biomass burning.


Examples of current COVID Cases in South Africa,  West and Southern Africa

South Africa (approximately 60000 cases)

In the next 10 days, the winter season will begin in South Africa.  The autumn season has seen a steady rise in COVID cases and the situation is likely to get worse as people are more likely to spend more time indoors because of colder temperatures and rainy conditions especially in Cape Town.   While you can recover from COVID, other confounding factors from the flu and poor air quality are likely to increase the risk of dying.    The number of reported daily positive cases in South Africa have increased from 698 cases on May 12 to 3359 cases on June 12.  The number of recorded deaths increased from 12 on May 11 and 70 as of June 12.


The Democratic Republic of Congo (DRC) -(4600) and Angola (160)

The DRC and Angola are near each other but have very different COVID-19 reported loading.   Angola took early pre-emptive action to limit COVID-19 by closing borders and limiting international flights.

https://www.namibian.com.na/199267/archive-read/Angola-closes-borders-for-15-days


This may have helped reduce the numbers of its COVID-19 cases to a current value of 130 positive cases.  However, according to Worldometer, they have only conducted about 10000 tests.

The neighboring DRC on the other hand has an estimated 4700 cases with more than 100 new cases reported per day over the last month.  Both the DRC and Angola are in  the dry season with many active fires

June 12 Satellite estimated Fire in Southern Africa

Because of the fires, we expect that poor air quality is occurring and will continue over the next 3 months.  This is a red flag for those with respiratory or cardiovascular disease to be very careful and to keep face covered if poor air quality is detected.



West Africa 
Similar to Southern Africa, COVID-19 cases have risen since April.  We examine Ghana, Nigeria and Senegal, which have all opened their economies and governments to some degree.  Senegal never really completely shut down but had a night curfew.    Nigeria, Ghana and Senegal all have megacities that are growing and could possibly become epicenters like many cities in the United States.  Nigeria is West Africa's most populated nation with nearly 200 million inhabitants.  Senegal and Ghana are considerably smaller.

Nigeria (approximately 15000 cases).  
Has seen a steady increase in the numbers of COVID cases with more than 15,000 total cases and a steady increase in daily positive cases.

Ghana (approximately 11000 cases) -has more than 11 thousand cases with an earlier peak in early May and a steady number of cases since June.

Senegal (approximately 5000 cases) - has approximately 5,000 positive cases since March with a steady increase of more than 100 cases since early June.


Potential Environmental Impacts for West Africa 

The wet season began along the Gulf of Guinea countries such as  Nigeria and Ghana in mid-to-late March.  Last night there was rain in Senegal --which is a little early. 

With the wet season comes a set of vector-borne and water-borne diseases along with influenza.   In fact, the wet season tends to be the coolest (not very cold) but rain can limit activity and keep more people in the house.   Possible diseases once the rain began to fall (now through October)

- malaria
- yellow fever and Dengue
- influenza
-acute respiratory infection

Influenza and acute respiratory infection (pneumonia)  like mid-latitude countries occur during the coolest and wettest part of the year in West Africa.  A paper lead my colleague Dr. Toure from Senegal shows that the largest numbers of reported cases for adults and children during wet season under normal conditions during 2015-2016.

Influenza, acute respiratory infection, and vector/water-borne diseases could pose a serious threat to patients that come down with COVID-19.

The rainy season and the associated diseases could:

- Increase  transmission because of indoor activity with the wet season;
- Increased susceptibility by weakening immune systems if one is fighting off another disease;
- Produce a much higher burden on hospitals as they cope with COVID-19 patients;
- Make it difficult for people with influenza or acute respiratory disease to distinguish it from COVID-19.

After one or two months of dry weather, West Africa countries will have to deal with the burden of dust and biomass burning and Southern Africa will have to contend with the wet season.  Because the cases of COVID-19 were relatively small during the last dry season in West Africa and wet season in Southern Africa any prediction of what may be expected is highly uncertain.



Key things to remember for the African Continent over the next year:

1.  The virus is in full effect around the World;
2.  Mask, social distancing and hand washing should be followed no matter what the case;
3.  The capacity of the public health care system must be monitored very carefully as the increase in cases in locations such as India, Brazil and now South Africa shows that the number of cases can increase quickly;
4.  The situation will remain dangerous until a vaccine is available (2021-2022).


COVID-19 and the Caribbean and SE US

Poor air quality from the Saharan Air Layer (SAL) has already been detected in Senegal and Cabo Verde (see figure).  Over the next 2 months, millions of tons of dust will be transported across the Atlantic degrading air quality.  This will make people with respiratory, cerebrovascular, and cardiovascular diseases more susceptible to poor outcomes from COVID-19.  In addition, the Caribbean will have to prepare for rain associated with easterly waves and potentially tropical cyclones. 

Dust leaving the African Coast on June 12, 2020

The number of hurricanes is projected to be higher than normal, but let us hope that their impact is limited and not capable of becoming major storms like Hurricane Dorian.

https://cimss.ssec.wisc.edu/satellite-blog/wp-content/uploads/2019/09/190901_190902_goes16_infrared_Dorian_anim.gif

4th large Bodele outbreak since Saturday -- impact on human health likely but unknown. Monitoring/communication required!!

Tuesday noon dust identification over North Africa.  

This morning, the 4th large dust outbreak erupted from Chad this morning and has entered eastern Niger, Chad and soon Nigeria and Cameroon.   As mentioned earlier, the anomalous flow across the desert has triggered these dust events.  Nearly all of Nigeria, Benin, Togo, Ghana and Ivory Coast have been impacted.   Millions have been under unhealthy to hazardous air quality from high concentrations of PM2.5.   In the next two days, the dust will move westward and emerge off the coast of West Africa.  In the process, many more people from Mali to Cabo Verde may experience very poor air quality and airports will be subject to poor visibiity.

Identification of dust outbreaks on Sat (Red), Sunday (Green) and Monday (Purple)

Communicating these large and long-exposure hazards is required, especially that many countries having low public health capacity, a growing population and limited access to income.  It has been estimated that there are 780,000 premature deaths due to pollution and desert dust is the primary contributor.  Recently we published a paper (https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GH000214)  showing that desert dust is very high in Senegal and respiratory disease is also very high.   My good friend Karin recently published a paper showing how lung cells are destroyed in dusty environments (https://www.sciencedirect.com/science/article/pii/S0013935119306887?via%3Dihub)

and it may be the reason why lung-cancer is relatively high in Senegal, even for non-smokers.  

Communication requires real-time access to data for the public.  Currently, the amount of surface data available for any decisionmaker including an asthmatic person is not sufficient in Africa.   If you go to http://aqicn.org/map/world/ you would only see one station with real-time data in West Africa which is Bamako.  My colleagues in Senegal put out a daily bulletin about air quality conditions each day for the Dakar region.  But there are far too many places that receive no information.  

Over the past year, there are some in the community that using low-cost sensors (200-300 USD) to try and provide real-time data.  While these instruments cannot be compared to 100,000 USD state of the art equipment, they provide a measure of air quality and are used all around the globe.   The purple air sensors are a great example of this (https://www.purpleair.com/map). 

Since, June we are trying to build a network in West Africa (Senegal, Cape Verde, Angola...) but simple things such as continuous wifi and electricity make it a challenge.  We are working on solutions for those.  When there are dust events such as the current one, there is a need to know locally what happening.  But really it is hospitals, decisionmakers and the public that really need the information locally.    So the most populous nation in West Africa, Nigeria does not have enough local monitoring of PM to protect its population during the dry season.  

Purple Air Network, Tuesday, February 11, 2020

If this is 2020 and we really want to have clear vision, we need to use innovation to help solve the current set of environmental problems.  But communication and protecting the public against predictable hazards such as dust outbreaks is within reach.  We just need to commit to the right action.

Large dust outbreak threatens the respiratory health of more than 100 million over next 10 days

Over the next few days, large quantities of millions of pounds of dust from the Sahara desert will enter into Nigeria, Benin, Ghana, Togo and Cote d-Ivorie.   It will pose a serious health hazard to more than 100 million in this region, especially those with existing respiratory disease, the young and elderly.   While this may seem like the typical garden variety type of dust event it is not.  Why????

1.  Duration.  This event is expected to last at least 5 days followed by another dust event.

2.  Intensity.  Dust levels will reach hazardous levels

3.  Scale.  The dust will cover thousands of miles and impact large cities such as Lagos (18 million), Ibadan, Cotonou, Accra and Kumasi.  Additional dust sites will be activated and impact Niamey and eventually Ouagadougou, Bamako and Dakar.

4. Health Impacts.  Based on what we have seen this year, the dust particles are PM2.5 which is about 25 times smaller than a human hair.  These particles reach deep into the lung system causing problems for those who have COPD, Asthma or other respiratory problems.

5. Prior Exposure.  Most Guinea locations in Nigeria, Ghana, Togo, Benin and Cote d'Ivoire have experienced many hours of bad air quality since December.  The negative health effects are likely
evident even if not well reported.

What is at the root of this event and the earlier ones. 

Positive Phase of the North Atlantic Oscillation (NAO) - which yields a strong Azores high that migrates into North Africa.  This year, the NAO has been locked in a positive phase leading to dust transport across most of West Africa.

Depiction of Azores high moving over North Africa and transporting dust 

The positive NAO has also been responsible for very warm temperatures across Europe this winter.

washingtonpost.com/weather/2020/02/03/warmth-is-really-unheard-much-eastern-europe-including-helsinki-moscow-saw-warmest-january-record/


Over the next 14 days, the area of high pressure is expected remain strong as depicted in the GFS model for 72 hours.   This pattern will send dust from Chad into Nigeria.

GFS Sunday morning (Feb 9) forecast of sea level pressure and Anomaly. Red represents higher than normal pressure

This pattern is forecasted to persist over North Africa as shown by the ECMWF model for next Wednesday, Feb 12

ECMWF Wednesday (Feb 11, 2020) Afternoon forecast of sea level pressure and anomalies.

What this means, is that dust will continue to flow strongly from Chad into the Guinea coast and westward toward Niger, Mali and Senegal.  I have run the WRF regional model with dust and the forecast from Wednesday depicts lots 

of dust moving first into Nigeria tomorrow but eventually making its way across much of West Africa.  The model underpredicts the amounts of dust coming into locations like Accra, Lagos and Abidjan and these values will be much higher than shown.

Caption:  WRF depiction of PM10 dust concentration on Sat Feb 8 and Tuesday, Feb 11 2020.

Those colors in orange or red represent hazard dust levels and as a short term hazard represent a certain level of mortality (> 12 %).  By reference, the World Health Organization (WHO) recommends no more than 50 microgram per meter cubed in a 24 hour period.  It is likely that people will see 4-10 times this amount and for the smallest particles of PM2.5 will see greater 50 micrograms per meter cubed;  WHO recommends no more than 25 50 microgram per meter cubed in a 24 hour period.   Because the exposure may be significant it is recommended that 

1. Limit outdoor activity 

2. Close windows 

3.  Monitor the young, elderly and those with existing respiratory conditions

4.  WEAR a mask if you have one.

5.  Go to the hospital if you are feeling acute symptoms such as shortness of breath or chest pains.

Poor Air Quality across West Africa-- negative health outcomes expected.

Caption:  Satellite images of dust loading (Red) across West Africa afternoon Jan 3, 2020

Each winter, the Harmattan winds begin to blow from the Sahara Desert.  It carries dry air but also dust into large populations of West Africa.   We link dust concentrations to particulate matter and focus on PM2.5 which penetrates deep into the lungs.  The consequences are serious if you are asthmatic, have COPD and can cause strokes and heart attacks.   When the values of PM begin to increase, studies have shown that there will be an increase in mortality associated with listed diseases above (see chart).

PM concentrations and Air Quality along with mortality risk

Since January 1, high Particulate Matter ( dust concentrations) have occurred across West Africa. Senegal and Cabo Verde have seen the heaviest reported values in the north.   Some of the airports in Cabo Verde closed because of low visibility.  However, in the south, Ghana, Ivory Coast, Nigeria, Togo, Benin, have experiences high PM values since Christmas.  I am 100% sure that there have been morbidity and mortality in these locations in the past.

What is different now is that we are using cost-effective sensors to get a look at what is happening across West Africa in real-time.  This allows us to link the environment to health outcomes.   We have been developing a network (measurements) in Senegal, Gambia, Cabo Verde, Ivory Coast while others have been developing low-cost networks in Ghana, and Togo.  Together we get a sense of the air quality from good to hazardous, where the real-time colors correspond to air quality on the maps.
https://www.purpleair.com/map?opt=1/mAQI/a10/cC0#4.15/12.99/-22.89

US EPA Air Quality Standards for PM2.5 and PM10

Purple Air estimates of Air Quality for the morning of 3 January 2020

Causes of Dust Storms in West Africa. 
What is driving force behind the current set of dust events?  There are large sources of dust over Northern Africa.  Two of the biggest dust sources are Bodele (the largest in the World) located in Chad, and the Adrar region of Southern Algeria and northeast Mali.   The Azores high-pressure system which exists over the subtropical ocean and is part of the North Atlantic Oscillation (NAO).
During the winter, the Azores high moves into North Africa across the Sahara and while high pressure normally means sunny weather, over North Africa it also brings strong winds over the desert which then starts the sandblasting process.

Depiction of how the Azores high to drive a dust storm

What is happening now, is that high pressure is currently in place for all of North Africa.  The figure from GFS forecast strong high pressure in play.

GFS sea level pressure and anomalies across Africa 0000 UTC

This means winds will flow across Chad and drive westward flowing winds that send dust from East to West.   The dust will flow into Nigeria and lead to poor air quality over the next few days to week.

January 4, 2020 Visible and AOD position of dust.  Circled in red are Adrar and Bodele dust regions

What to do when there is poor air quality?
So what are the proper actions to take if you suspect or see that the air quality is poor (unhealthy to hazardous)?

1.)  If air quality is poor, limit your time outdoors and your physical activity.

2.)  Wear a mask if you have one until conditions get better.  This may not seem cute, but you are not sick!! You are trying not to get sick. 

3.) Pay attention to the elderly, and young children. 

4.)  If breathing problem begin or you feel chest pain go to the Emergency Room to be checked
by a doctor.


Other Sources of Poor Air Quality 

On the continent, there are multiple sources of pollution that can make air quality poor.  In rural areas, seasonal biomass burning which is tied to agricultural practices can create very poor quality. Large megacities are now becoming problematic because of traffic, waste, and industry.   The waste that is being generated is burned in large waste sites or locally leading poor air quality.  Traffic has become worse with no end in sight.  Many of the cars use low-quality diesel fuel with high sulfur content making pollution horrible in places like Dakar, Senegal.  The so-called modernization of Africa is leading to pollution-causing industries, like cement and coal-burning power plants. 

Sources of pollution including Traffic, Industrial pollution and burning of trash

Finally, there is indoor pollution from cooking.  We know this is bad for family members who use biomass or charcoal, especially in poorly ventilated buildings. 

We need to predict, communicate and protect individuals from air pollution for success.  Ultimately, government policy is required to address pollution issues.  Everyone who has a friend or family member has something to gain from improving air quality.