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Variation of Aerosol Pollution in Peru during the Quarantine Due to COVID-19

(IJACSA) International Journal of Advanced Computer Science and Applications,
Vol. 11, No. 4, 2020
47 | Page
Variation of Aerosol Pollution in Peru during
the Quarantine Due to COVID-19
Avid Roman-Gonzalez1*, Natalia I. Vargas-Cuentas2
Image Processing Research Laboratory (INTI-Lab), Universidad de Ciencias y Humanidades, Lima, Peru1, 2
Aerospace Sciences & Health Research Laboratory (INCAS-Lab), Universidad Nacional Tecnológica de Lima Sur1
AbstractDue to COVID-19, which is a type of pneumonia
produced by a coronavirus family virus, the Peruvian
government has decreed mandatory social isolation. This
isolation is extended until 26 April 2020. Due to this situation,
people must stay at home and only go out to make purchases to
cover basic needs. This situation, between other things, probably
causes pollution reduction that is important for our ecosystem. In
Peru, there is not a measurable way to quantify the impact of
social isolation on air pollution. The present work aims to show
more objectively how much decrease the aerosol pollution in
Peru. For this purpose, one uses remote sensing data from
Copernicus Data Hub of the European Space Agency,
specifically, Sentinel-5 Precursor satellite. The results show an
essential reduction of aerosol pollution in different regions of
Peru, especially in Lima and the Amazon regions.
KeywordsCOVID-19; coronavirus; pollution; Sentinel-5P;
COVID-19 is a disease that started in December 2019 in
Wuhan, China [1]. COVID-19 is a type of pneumonia
produced by a virus belonging to the coronavirus family that
affects the pulmonary alveoli and generates respiratory failure
[1, 2]. According to reports from the World Health
Organization (WHO) [3], for 22 April 2020, after China, the
outbreak has globally reached 2 471 136 cases and 169 006
deaths. In Fig. 1, one can observe a global map about the
impact of the COVID-19 around the World.
Due to the rapid spread of contagion, on 11 March 2020,
WHO declared COVID-19 as a pandemic. This declaration
was in an opening address by the WHO General Director for a
press conference [4].
In Peru, the first case was reported by President Martin
Vizcarra at a press conference on Friday, 6 March, 2020 [5].
The evolution in Peru from the first case of COVID-19 has an
exponential trend and it is shown in Fig. 2.
Fig. 2 shows the evolution of total cases (curve in blue),
new cases per day (bend in gray), total cases recovered (curve
in cyan), active cases (line in intense blue), and total deaths
(curve in red). Active cases are calculated as the subtraction of
the total cases, minus the recovered cases, minus the deceased.
Deaths curve is according to right axis, and the other curves
are according to left axis. Currently, at 22 April 2020, Peru
has 19 250 total cases, 7 027 recovered cases, 11 693 active
cases, and 530 deaths.
Due to this situation of the first cases of COVID-19 in
Peru and to try to avoid an exponential growth in the number
of cases, the President of Peru, Martin Vizcarra, announced
the Supreme Decree that declares a State of National
Emergency for 15 days [6, 7]. This State of Emergency was
reported on March 15, 2020. This declaration implies, among
other things, the restriction of the exercise of constitutional
rights related to personal liberty and security, the inviolability
of the home, and the freedom of meeting and transit in the
territory. In this State of Emergency, people are in quarantine;
however, the supply of food and medicine is guaranteed.
Although the increase in the number of cases has been
somewhat halted compared to projections established with the
experience of other countries, the Peruvian government has
decided to extend the State of Emergency until April 26, 2020
Fig. 1. Countries with Reported Cases of COVID-19, 22 April 2020,
®WHO, [3].
Fig. 2. Evolution of the COVID-19 Cases in Peru, 22 April 2020.
*Corresponding Author
(IJACSA) International Journal of Advanced Computer Science and Applications,
Vol. 11, No. 4, 2020
48 | Page
In this State of Emergency, people have remained in their
homes most of the time. So it has been possible to visualize
that the natural ecosystem has recovered. This recovery
implies a cleaner sky, clearer waters, return of marine spices
to the Sea of Grau, among other aspects [9].
Regarding all the aforementioned, the objective of this
work is to measure in a more objective and visible way the
reduction of air pollution by aerosols in Peru.
Aerosols are pollutants because they contain substances
that, in contact with sunlight, produce polluting gases.
Changes in weather may occur. It also affects people's health
Remote sensing is an excellent option to assess air
pollution by taking a global view of the area to be analyzed.
Measuring aerosols is a good option, as does Gitahi et al. [11],
who use high-resolution satellite images such as Sentinel-2
images. In that work, they extract the Aerosol Optical Depth
(AOD) from the Sentinel-2 images and compare them with
measurements from 2 Aerosol Robotic Network (AERONET)
stations for the city of Munich, Germany. The results they
obtained show a strong consistency between both analyses,
which shows the feasibility of using Sentinel-2 satellite
images for this type of purpose.
Another work that uses Lansat-8 and Sentinel-2 images is
the one presented by Li et al. [12]. In that work, the data
obtained from the satellite images are also compared with the
data from the AERONET stations. The results they got show
that the AOD obtained from the Sentinel-2 images have better
precision than the AOD from the Landsat-8 images.
On the other hand, Theys et al. [13] use Sentinel-5
Precursor (also called as Sentinel-5P) images for monitoring
volcanic gases.
As can be seen, satellite images can be used effectively in
monitoring air pollution, and having a platform to interact and
to access images, like the one presented in [14], could be a
great help.
The continuation of this research work is as follows,
Section II shows the methodology to be followed and the used
tool for the analysis, Section III presents the obtained results,
and finally, Section IV gives the discussion and conclusions of
the work.
For this research work, one will use satellite images from
the Copernicus program of the European Union, specifically
Sentinel-5 Precursor (Sentinel-5P) images.
The methodology to be followed will be based on the
works presented in [13, 15]. The idea is to collect a database
of images of the region of interest (Peru); read the images and
values get from the satellite; finally, mapping the result and
compare them.
In the following sub-section, one describes the followed
A. Sentinel-5 Precursor Images
Also known as Sentinel-5P, it was launched on October
13, 2017. Sentinel-5P's main objective is the atmospheric
monitoring of our planet [16, 17].
The Sentinel-5P payload is the TROPOspheric Monitoring
Instrument (TROPOMI). TROPOMI is a hyperspectral
spectrometer. Fig. 3 is an artistic representation of the satellite
Some specifications of the mission that we can mention
are the following [15, 16]:
Sentinel-5P will provide measurements of:
NO_2 (nitrogen dioxide)
SO_2 (sulfur dioxide)
Mission Orbit:
Orbit Type: Sun-synchronous, polar
Orbit Height: 824 km
To download Sentinel-5P images and create the database,
one uses the Copernicus Open Access Hub of the European
Space Agency (ESA). In Fig. 4, one can see a screenshot of
the Hub.
Fig. 3. Sentinel-5P © ESA.
Fig. 4. Copernicus Open Access Hub.
(IJACSA) International Journal of Advanced Computer Science and Applications,
Vol. 11, No. 4, 2020
49 | Page
For the present work, images measuring Aerosol
(L2__AER_AI), of the level L2, have been downloaded from
March 11 to March 26, 2020. In other words, one has five
images before quarantine and ten images during the
For the processing and visualization of the images, the
VISAN tool will be used. VISAN is a cross-platform for
visualization and analysis applications for atmospheric data.
VISAN uses the Python language as the means through which
one can provide commands. The Python interfaces for CODA
and HARP are included, so one can directly ingest product
data from within VISAN. Also, VISAN delivers some robust
visualization functionality for 2D and world plots [15]. Fig. 5
shows a screenshot of the principal windows of the VISAN
Fig. 5. VISAN Platform.
For this project, the version 4.0 of the VISAN and the
version 3.8.2 of Python.
One uses commands like: harp.import_product and wplot
among others to read, analyze, and mapping the obtained
After processing and analysis, the visualization can be
seen in Fig. 6. It can be seen that before the obligatory
isolation measurement, the levels of southern surface wind
velocity (m / s) in Peru had few cyan regions. Ten days after
the declaration of a state of national emergency, the cyan areas
have increased. Fig. 6 is a heat map where the red zone
represents polluted areas, and cyan and blue areas represent
areas with less pollution.
The highest levels are seen in shades of red, and the lowest
levels are seen in shades of blue.
Fig. 6. Variation of Aerosol Contamination in Peru Due to Quarantine by
As can be seen in the results obtained after the processing,
analysis, and visualization of Sentinel-5P images, air pollution
in Peru during the first ten days of quarantine due to COVID-
19, has decreased. Some regions have a more significant
decrease than others, but in general, a reduction can be noticed
throughout the country. This decrease is essential for the
planet. As well as in Peru, in other countries, there has also
been a decrease in pollution. This situation allows the
ecosystem to recover and nature to breathe.
The decrease will be much more noticeable as the days go
by, as already mentioned, the quarantine in Peru was extended
until April 26.
It is also possible to monitor SO2, O3, NO2, Methane,
among other parameters. In a future work the idea is to
analyse all parameters.
The main contribution of this work is to demonstrate the
positive impact of quarantine on the environment objectively.
The evolution of the cases of COVID-19 in Peru shows a
small reduction in the trend of change for the last days. New
cases per day are around 1000. In the previous week, there is a
slow growth of recovered people, so active cases continue to
increase. The increase in the number of cases is also due to the
increase in the number of tests, since in Peru molecular tests
and rapid tests are currently being used.
[1] Xu, Zhe, et al. "Pathological findings of COVID-19 associated with
acute respiratory distress syndrome." The Lancet respiratory medicine
[2] Chen, Huijun, et al. "Clinical characteristics and intrauterine vertical
transmission potential of COVID-19 infection in nine pregnant women:
a retrospective review of medical records." The Lancet 395.10226
(2020): 809-815.
(IJACSA) International Journal of Advanced Computer Science and Applications,
Vol. 11, No. 4, 2020
50 | Page
[3] World Health Organization. "Coronavirus disease 2019 ( COVID-19):
situation report, 93." (2020).
[4] WHO Director-General's opening remarks at the media briefing on
COVID-19 - 11 March 2020 [Online] Available at:
[5] Martín Vizcarra confirmó el primer caso de coronavirus en el Perú
[Online] Available at:
[6] Gobierno declaró estado de emergencia por coronavirus en Perú
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[7] Decreto Supremo que declara Estado de Emergencia Nacional por las
graves circunstancias que afectan la vida de la Nación a consecuencia
del brote del COVID-19 [Online] Available at:
[8] Presidente de Perú anuncia extensión de cuarentena hasta el 26 de abril
en busca de frenar el coronavirus [Online] Available at:
[9] Delfines aparecen en playa La Herradura de Chorrillos tras aislamiento
de personas por la cuarentena [VIDEO] [Online] Available at:
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[11] Gitahi, Joseph, Michael Hahn, and Andres Ramirez. "High-resolution
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[12] Li, Zhongbin, et al. "Evaluation of Landsat-8 and Sentinel-2A aerosol
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[13] Theys, N., et al. "Global monitoring of volcanic SO degassing with
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[14] Roman-Gonzalez, Avid, and Natalia Vargas-Cuentas. "Designing A
Web Platform Paradigm for Satellite Images based on user Preferences."
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(version 1.1). Retrieved from RUS Lectures at https://rus-
[16] Sentinel-5P [Online] Available at:
[17] Zeng, Jian, et al. "Air Quality Satellite Monitoring by TROPOMI on
Sentinel-5P." (2018).
... Cuentas, 2020). Apesar de se tratar de um quadro extremo, isso pode indicar que a ampla adoção do "home office" pode gerar, mantidas as devidas proporções, algum impacto positivo sobre condições de tráfico e poluição, assim como percebido pelo entrevistado.Lawson, Petersen, Cousins, & Handfield, 2009). ...
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... Some examples could be found at [6][7][8][9][10]. • Monitoring environmental factors that affect people's health, such as air quality [11], traffic, and dryness of water bodies, among others. • Provide access to healthcare for remote, lowincome locations using telemedicine technology. ...
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The present economy primarily makes use of space-based communication in servicing the health sector. This scenario is mostly in the use of routine communication technologies, and also has essential applications in addressing issues of telemedicine and disaster medicine. Earth observation data is also used to assist public health data collection and campaigns. Space-based applications are well placed to reduce further the health inequities surrounding access to healthcare, both as a result of geography and resource availability. Earth observation satellites are increasingly capable of providing high visual and temporal resolution data that can hope to serve health issues related to demographics, the migration of people, climate change, and the vectors of infectious disease. Space-based life sciences also offer essential medical research into widely prevalent and incident conditions. Non-space actors can engage these solutions by using the available services and data. Possible challenges that may be faced are incomplete access to communication satellites that prevents the establishment of crucial telecommunication networks in rural and remote areas, and the inconsistency and lack of cooperation amongst providers of Earth observation services in the types of data collected. This work tries to show the frameworks that can be developed to help global health; through the aggregation of different service-based and data resources, and the distillation of global health issues into goals that these resources can appropriately address. This process can achieve international collaboration by broadening the criteria for access to data, by encouraging the advancement of relevant technology, and by helping new space leaders to prioritize practical cooperation in the face of global issues. Non-space actors should work together by defining clear aims in the use of space-based communication and Earth observation data. By outlining global health goals with distinct indicators of performance, the use and access to such resources will be made more efficient to achieve Sustainable Development Goals (SDG).
... No entanto, há registros sobre a redução da poluição do ar, das águas de rio e do mar em algumas cidades, como consequências do isolamento social (Roman-Gonzalez;Vargas-Cuentas,2020;Ormaza-González;Castro-Rodas,2020 ....11,18,55,56,64,65,66,70,72,75,77,78,79,80,81,82,84,86,87,88,91,97 alimentação ........................ 11,15,26,27,94,95 B Brasil ...10,11,12,13,14,15,17,22,23,28,29,30,31,32,33,34,35,36,38,41,43,44,45,46,49,50,53,54,55,56,60,62,63,65,67,72,73,74,76,77,78,79,80,81,82,84,85,88,89,90,91,92 24,26,48,84,85,88,90 contato 11,13,15,16,18,28,41,43,50,55,56,57,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,26,28,29,32,33,35,37,38,39,41,42,44,45,46,47,48,49,50,53,54,55,56,57,58,59,60,61,63,65,66,67,73,78,80,82,85,86,90,92,93,96 .... 9, 16, 23, 25, 26, 28, 29, 32, 33, 35, 36, 41, 42, 44, 45, 46, 47, 48, 64, 82, 83 18, 72, 74, 75, 76, 81, 90, 91 I internet 16, 27, 28, 32, 33, 34, 35, 36, 37, 41, 42, 46, 47, 59, 95 isolamento social . 11, 12, 15, 16, 17, 19, 27, 35, 36, 39, 43, 44, 66, 95, 97 11, 16, 19, 22, 48, 53, 54, 56, 57, 58, 63, 78, 79, 80, 83, 86, 87, 91 saúde pública ................ 12, 45, 65, 67, 72, 77, 78 sintomas ........................ 12, 14, 15, 39, 57, 92 . ...
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Introduction COVID-19 is a pandemic that affected humans’ lives and activities through the year 2020 in a way that was not witnessed in recent years. Many governments declared a complete lockdown as a try to stop the transmission of the disease. This lockdown resulted in a good recovery in environmental health, where air pollutants levels dramatically decreased. Theory There are two relations between air pollution and COVID-19, one is before the disease spread, and the other is after. Before the disease spread, many areas had high levels of contaminants in the air due to industrial activities, transportation, and human density. These areas had the highest infection rates and death cases. This could be attributed to two reasons, the aerosol could help to spread the virus at a higher rate, and air pollutants could negatively affect peoples’ lungs, which assisted the virus in attacking the patients brutally. Results After the disease spread, the lockdown that was applied in the major industrial countries led to a decrease in the pollutants levels and an increase in the ozone level in the air. This lockdown improved the air quality worldwide to a level that all political conferences and agreements could not reach. In this review, we are showing the impact of COVID-19 on air pollutants in different countries. Summary This paper provides information about pollutants' influence on human and environmental health that other researchers obtained in different areas of the globe before and after the pandemic. This could give ideas about the impact of humans on the environment and the possible ways of recovering the environment's health.
Due to the COVID-19 pandemic, the situation at the international level is critical. COVID-19 is a type of pneumonia due to a coronavirus family. Due to this situation, like many countries, the Peruvian government has decreed mandatory social isolation, which was in effect through June 30, 2020. According to this decree, people were to stay at home and only go out to cover basic needs. After more than 50 days, some images and videos presented in different communication channels, show that animals and vegetation recover their space on the planet. Pollution reduction is probable too, which is vital for our ecosystem. However, there is no measurable way to quantify the impact of social isolation on air pollution in Peru. Thus, the present research work aims to show more objectively how much there has been a decrease in air pollution in Peru. The idea is to analyze the quantity of ozone, nitrogen dioxide, sulfur dioxide, formaldehyde, aerosol, carbon monoxide, methane, and clouds in the air. For this purpose, remote sensing data is used from the Copernicus Data Hub of the European Space Agency, specifically, the Sentinel-5 Precursor satellite. The obtained results show a reduction in air pollution in different regions of Peru.
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The world is going through a period of calamity, a pandemic caused by the coronavirus. The situation began in China and has spread to its world surroundings. A means of combat attributed to society was isolation and social distancing, which could relate to the environment. The objective of this work is a systematic comparative review of the positive and negative impacts that the pandemic has caused on the environment. A systematic survey was conducted at PUBMED, Scielo and Google Academic, in the months of August to October 2020 using indexers. There are several positive points with pandemic related to the environment, however the indiscriminate use of materials has increased, being a negative point. It is perceived that the environment breathed with the measure of social isolation, but still needs various care.
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and the out-of-sample period ranges over the period November 2020-April 2021. The residuals and forecast evaluation criteria (Error, MSE and MAE) of this model indicate that the model is quite stable. The results of the study indicate that daily COVID-19 cases will continue to decline over the out-of-sample period until an equilibrium level of about 104 cases per day is reached somewhere around 11 January 2021. It is important for the Peruvian government to note that the projected decline in COVID-19 cases is a product of the current prevention and control measures being consistently taken. We therefore encourage the government to continue making sure that these measures are taken seriously, especially by the general public.
The COVID-19 pandemic and resulting shelter-in-place measures led to widespread adoption of remote work policies and temporary business closures or operation curtailments, disrupting typical commuting patterns. This study investigates how these sudden shifts in traffic patterns affected near-road NO and NO2 concentrations in California. We used (1) near-road air pollution data from the U.S. Environmental Protection Agency's AirNow database, (2) passenger and heavy-duty traffic data from the Caltrans Performance Monitoring System, and (3) weather data from MesoWest between January 1 and April 30 during the years 2017-2020 to model NO and NO2 concentrations as functions of highway traffic and meteorology. We then simulated NO and NO2 under business-as-usual traffic conditions and compared modeled data to observed values. Weekday passenger traffic significantly declined in Northern and Southern California by 29% and 24%, respectively. As a result, Northern and Southern California near-road locations experienced statistically significant declines in NO concentrations of 35% and 32% and in NO2 concentrations of 15% and 29%, respectively, compared to modeled estimates. As a natural experiment, our findings demonstrate that reduced vehicle activity significantly improved air quality, contributing to the body of evidence linking shelter-in-place measures and cleaner air.
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Over the last four decades, space-based nadir observations of sulfur dioxide (SO2) proved to be a key data source for assessing the environmental impacts of volcanic emissions, for monitoring volcanic activity and early signs of eruptions, and ultimately mitigating related hazards on local populations and aviation. Despite its importance, a detailed picture of global SO2 daily degassing is difficult to produce, notably for lower-tropospheric plumes, due largely to the limited spatial resolution and coverage or lack of sensitivity and selectivity to SO2 of current (and previous) nadir sensors. We report here the first volcanic SO2 measurements from the hyperspectral TROPOspheric Monitoring Instrument (TROPOMI) launched in October 2017 onboard the ESA’s Sentinel-5 Precursor platform. Using the operational processing algorithm, we explore the benefit of improved spatial resolution to the monitoring of global volcanic degassing. We find that TROPOMI surpasses any space nadir sensor in its ability to detect weak degassing signals and captures day-to-day changes in SO2 emissions. The detection limit of TROPOMI to SO2 emissions is a factor of 4 better than the heritage Aura/Ozone Monitoring Instrument (OMI). Here we show that TROPOMI SO2 daily observations carry a wealth of information on volcanic activity. Provided with adequate wind speed data, temporally resolved SO2 fluxes can be obtained at hourly time steps or shorter. We anticipate that TROPOMI SO2 data will help to monitor global volcanic daily degassing and better understand volcanic processes and impacts.
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In urban environments, aerosol distributions may change rapidly due to building and transport infrastructure and human population density variations. The recent availability of medium resolution Landsat-8 and Sentinel-2 satellite data provide the opportunity for aerosol optical depth (AOD) estimation at higher spatial resolution than provided by other satellites. AOD retrieved from 30 m Landsat-8 and 10 m Sentinel-2A data using the Land Surface Reflectance Code (LaSRC) were compared with coincident ground-based Aerosol Robotic Network (AERONET) Version 3 AOD data for 20 Chinese cities in 2016. Stringent selection criteria were used to select contemporaneous data; only satellite and AERONET data acquired within 10 min were considered. The average satellite retrieved AOD over a 1470 m × 1470 m window centered on each AERONET site was derived to capture fine scale urban AOD variations. AERONET Level 1.5 (cloud-screened) and Level 2.0 (cloud-screened and also quality assured) data were considered. For the 20 urban AERONET sites in 2016 there were 106 (Level 1.5) and 67 (Level 2.0) Landsat-8 AERONET AOD contemporaneous data pairs, and 118 (Level 1.5) and 89 (Level 2.0) Sentinel-2A AOD data pairs. The greatest AOD values (>1.5) occurred in Beijing, suggesting that the Chinese capital was one of the most polluted cities in China in 2016. The LaSRC Landsat-8 and Sentinel-2A AOD retrievals agreed well with the AERONET AOD data (linear regression slopes > 0.96; coefficient of determination r2 > 0.90; root mean square deviation < 0.175) and demonstrate that the LaSRC is an effective and applicable medium resolution AOD retrieval algorithm over urban environments. The Sentinel-2A AOD retrievals had better accuracy than the Landsat-8 AOD retrievals, which is consistent with previously published research. The implications of the research and the potential for urban aerosol monitoring by combining the freely available Landsat-8 and Sentinel-2 satellite data are discussed.
Background: Previous studies on the pneumonia outbreak caused by the 2019 novel coronavirus disease (COVID-19) were based on information from the general population. Limited data are available for pregnant women with COVID-19 pneumonia. This study aimed to evaluate the clinical characteristics of COVID-19 in pregnancy and the intrauterine vertical transmission potential of COVID-19 infection. Methods: Clinical records, laboratory results, and chest CT scans were retrospectively reviewed for nine pregnant women with laboratory-confirmed COVID-19 pneumonia (ie, with maternal throat swab samples that were positive for severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) who were admitted to Zhongnan Hospital of Wuhan University, Wuhan, China, from Jan 20 to Jan 31, 2020. Evidence of intrauterine vertical transmission was assessed by testing for the presence of SARS-CoV-2 in amniotic fluid, cord blood, and neonatal throat swab samples. Breastmilk samples were also collected and tested from patients after the first lactation. Findings: All nine patients had a caesarean section in their third trimester. Seven patients presented with a fever. Other symptoms, including cough (in four of nine patients), myalgia (in three), sore throat (in two), and malaise (in two), were also observed. Fetal distress was monitored in two cases. Five of nine patients had lymphopenia (<1·0 × 10⁹ cells per L). Three patients had increased aminotransferase concentrations. None of the patients developed severe COVID-19 pneumonia or died, as of Feb 4, 2020. Nine livebirths were recorded. No neonatal asphyxia was observed in newborn babies. All nine livebirths had a 1-min Apgar score of 8-9 and a 5-min Apgar score of 9-10. Amniotic fluid, cord blood, neonatal throat swab, and breastmilk samples from six patients were tested for SARS-CoV-2, and all samples tested negative for the virus. Interpretation: The clinical characteristics of COVID-19 pneumonia in pregnant women were similar to those reported for non-pregnant adult patients who developed COVID-19 pneumonia. Findings from this small group of cases suggest that there is currently no evidence for intrauterine infection caused by vertical transmission in women who develop COVID-19 pneumonia in late pregnancy. Funding: Hubei Science and Technology Plan, Wuhan University Medical Development Plan.
Life on Earth is critically dependent upon the continuous cycling of water between oceans, continents and the atmosphere. Precipitation (including rain, snow, and hail) is the primary mechanism for transporting water from the atmosphere back to the Earth's surface. It is also the key physical process that links aspects of climate, weather, and the global hydrological cycle. Changes in precipitation regimes and the frequency of extreme weather events, such as floods, droughts, severe ice/snow storms, monsoon fluctuations and hurricanes are of great potential importance to life on the planet. One of the factors that could contribute to precipitation modification is aerosol pollution from various sources such as urban air pollution and biomass burning. Natural and anthropogenic changes in atmospheric aerosols might have important implications for precipitation by influencing the hydrological cycle, which in turn could feed back to climate changes. From an Earth Science perspective, a key question is how changes expected in climate will translate into changes in the hydrological cycle, and what trends may be expected in the future. We require a much better understanding and hence predictive capability of the moisture and energy storages and exchanges among the Earth's atmosphere, oceans, continents and biological systems. This book is a review of our knowledge of the relationship between aerosols and precipitation reaching the Earth's surface and it includes a list of recommendations that could help to advance our knowledge in this area.
High-resolution urban aerosol monitoring using Sentinel-2 satellite images
  • Joseph Gitahi
  • Michael Hahn
  • Andres Ramirez
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