Dissertations / Theses on the topic 'Covid 19 and air pollution'

Thesis advisor: Yasmin Zaerpoor
The Coronavirus pandemic has cast a new light on the intersection of environmental justice and public health, as communities of color and low-income communities have experienced greater rates of infection and mortality due to the Covid-19 pandemic. These inequalities can be attributed to a multitude of injustices. I investigate the impact that air pollution has had on COVID-19 incidence within Massachusetts, while also investigating other possible correlating factors. I use a regression model to consider the impact of air pollution, population density, race, income, age, and education on COVID-19 positivity rates in Massachusetts. In this study, I found that air pollution, population density, and the percentage of Hispanic population in a given community were all statistically significant in a linear regression model. Further research would be needed to investigate whether the coefficient on Hispanic population is conclusive. It is possible that the significant coefficient is picking up variables that are not included in this regression, namely the percentage of essential workers or access to healthcare
Thesis (BA) — Boston College, 2021
Submitted to: Boston College. College of Arts and Sciences
Discipline: Departmental Honors
Discipline: Environmental Studies

With the ongoing COVID-19 pandemic being spread all over the world, lockdown measures are being implemented making air pollution levels go down in several countries. In this context, the air quality changes in the highly populated and trafficked Brazilian states of Sao Paulo (SP) and Rio de Janeiro (RJ) are hereby going to be addressed using a combination of satellite and ground-based data analysis. We explored nitrogen dioxide (NO2) and particulate matter (PM2.5) daily levels for the month of May during different years within 2015-2020. Daily measurements of NO2 column concentrations from the Ozone Monitoring Instrument (OMI) aboard NASA's Aura satellite were also gathered and averaged decreases of 42% and 49.6% were found for the year of 2020 compared to previous averaged 2015-2019 years. In parallel to the NO2 column retrieval, the ground-based data, measured by the Brazilian States Environmental Institutions, is analyzed, and correlated with satellite retrievals. Correlation coefficients between column and ground-based concentrations were 77% and 53% in SP and RJ, respectively. It was found a 13.3% (p-value = 0.099) and 18.8% (p-value = 0.077) decrease in NO2 levels for SP and RJ, respectively, in 2020 compared to 2019. For PM2.5, no significant change was observed for the same time period in the SP region, although the high number of fire burnings in the Southeast region seemed to be affecting PM2.5 levels. In addition to natural emissions (fire burnings), the combined data was also evaluated taking meteorological parameters, such as temperature and wind speed, into account. No interference of weather or fire was found in 2020 NO2 ground levels compared to previous years, This integrated analysis is innovative and has yet to be more explored in Brazilian studies. This is true specifically because the ground-based stations are spatially and temporally sparse in Brazil.
Master of Science
This study aims to explore satellite data applied to the lockdown context resultant from the COVID-19 pandemic in Brazil. Satellite data usage in air quality management is yet to be explored to its full potential. Two highly populated states were chosen: Sao Paulo (SP) and Rio de Janeiro (RJ). Local governments have been imposing limitations on private and public vehicle circulation, inducing a decrease in atmospheric pollutant levels, specifically nitrogen dioxide (NO2), which is directly emitted to the air by fuel combustion. NO2 is also short-lived in the atmosphere, so its variation within days can be easily captured. PM2.5, a category of fine inhalable particles, can be produced by wildfires, in addition to fuel burning and mechanical processes such as resuspension by cars. Here we retrieved daily NO2 vertical column densities for the month of May within the 2015-2020 years from the OMI instrument onboard of NASA's Aura satellite. Ground daily NO2 and PM2.5 measurements were also collected from local environmental agencies. Results showed an average 42% decrease of the NO2 column values in SP in 2020 compared to 2015-2019. The decrease was 49.6% in RJ for the same timeframe. Correspondent surface data showed a decrease of 13.3% (p-value = 0.099) and 18.8% (p-value = 0.077) during 2020 compared to 2019 in SP and RJ stations, respectively. No significant divergence in PM2.5 values was found between 2019 and 2020. Finally, weather data was added to the pollutant analysis. PM2.5 concentrations were associated with wildfires, while the NO2 levels found in 2020 for SP and RJ were attributed to local lockdown decrees. Satellite retrievals showed significant potential in filling out ground datasets, correlating with the SP and RJ surface data in 77% and 53%, respectively.

1. Abate, Megersa, Panayotis Christidis and Alloysius Joko Purwanto (2020), “Government support to airlines in the aftermath of the COVID-19 pandemic”, Journal of Air Transport Management 89:101931, URL: https://doi.org/10.1016/j.jairtraman.2020.101931 2. IEA (2020), “Changes in transport behaviour during the Covid-19 crisis”, International Energy Agency, Paris, URL: https://www.iea.org/articles/changes-in-transport behaviour-during-the-covid-19-crisis 3. International Transport Forum (2020), “Restoring air connectivity under policies to mitigate climate change”, COVID-19 Transport Brief, URL: https://www.itf oecd.org/sites/default/files/air-connectivity-covid-19.pdf 4. International Transport Forum (2018), “Government support measures for domestic air connectivity”, Case-Specific Policy Analysis Reports, URL: https://www.itf oecd.org/government-support-measures-domestic-air-connectivit
Around 58% of tourists arrive at their destination by air and the stop in air traffic has created a massive negative effect on that industry as well. Over $630 billion in reduced GDP benefits from air travel-related tourism will be matched with 26.4 million jobs lost. But tourism in a wider sense is also very hard-hit, with analysis suggesting the pandemic could translate into a drop of 850 million to 1.1 billion international tourists and a loss of $910 billion to $1.2 trillion in export revenues from tourism, putting 100 to 120 million direct tourism jobs at risk.
Близько 58% туристів прибувають до місця призначення повітряним транспортом і зупинкою в повітрі транспорт також створив значний негативний вплив на цю галузь. Понад 630 мільярдів доларів у зменшенні ВВП вигоди від туризму, пов'язаного з повітряними подорожами, будуть відповідати 26,4 мільйона втрачених робочих місць. Але туризм у ширшому розумінні також дуже постраждалий, якщо аналізувати припускаючи, що пандемія може призвести до падіння від 850 до 1,1 мільярда міжнародних туристів та втрати від експорту від 910 млрд. до 1,2 трлн. доларів туризму, піддаючи ризику 100-120 мільйонів прямих туристичних робочих місць.

Досліджено вплив COVID-19 на авіаційні перевезення в світі (міжнародні та внутрішні перевезення). Проаналізовано регіональний розподіл міжнародних авіапасажирів у світі в контексті пандемії COVID-19.
Исследовано влияние COVID-19 на авиационные перевозки в мире (международные и внутренние перевозки). Проанализировано региональное распределение международных авиапассажиров в мире в контексте пандемии COVID-19.
The impact of COVID-19 on air transportation in the world (international and domestic transportation) has been studied. The regional distribution of international air passengers in the world in the context of the COVID-19 pandemic is analyzed.

‘‘SARS-CoV-2’’ which is responsible for the current pandemic of COVID-19 disease was first reported from Wuhan, China, on 31 December 2019. Since then, to prevent its propagation around the world, a set of rapid and strict countermeasures have been taken. While most of the researchers around the world initiated their studies on the Covid-19 lockdown effect on air quality and concluded pollution reduction, the most reliable methods that can be used to find out the reduction of the pollutants in the air are still in debate. In this study, we performed an analysis on how Covid-19 lockdown procedures impacted the air quality in selected cities i.e. New Delhi, Diepkloof, Wuhan, and London around the world. The results show that the air quality index (AQI) improved by 43% in New Delhi,18% in Wuhan,15% in Diepkloof, and 12% in London during the initial lockdown from the 19th of March 2020 to 31st May 2020 compared to that of four-year pre-lockdown. Furthermore, the concentrations of four main pollutants, i.e., NO2, CO, SO2, and PM2.5 were analyzed before and during the lockdown in India. The quantification of pollution drop is supported by statistical measurements like the AVOVA Test and the Permutation Test. Overall, 58%, 61%,18% and 55% decrease is observed in NO2, CO,SO2, and PM2.5 concentrations, respectively. To check if the change in weather has played any role in pollution level reduction or not we analyzed how weather factors are correlated with pollutants using a correlation matrix. Finally, machine learning regression models are constructed to assess the lockdown impact on air quality in India by incorporating weather data. Gradient Boosting is performed well in the Prediction of drop-in PM2.5 concentration on individual cities in India. By comparing the feature importance ranking by regression models supported by correlation factors with PM2.5.This study concludes that COVID-19 lockdown has a significant effect on the natural environment and air quality improvement.

Adverse health impacts of ambient air pollution and noise have been reported previously. However, many published studies were in adults or aged population, little attention has been paid to children and in particular to noise and the potential combined effect with air pollution. In addition, we considered health parameters, which are underinvestigated so far. In our study, we explored associations between ambient air pollution and noise with blood pressure (BP), and exhaled nitric oxide (eNO) in school-aged children, using data from two German birth cohorts. Noise levels within a 50m buffer around each participant’s home address were assessed using geographic information system. Exposure estimates of annual average concentrations of air pollution for each participant’s residence were calculated using a land use regression model. Short-term concentrations of air pollution were collected from background monitoring sites. Information on BP and eNO was collected during a physical examination at the 10-year follow-up of the cohorts. We studied the health impacts of ambient air pollution and noise in children from three different aspects. The association between traffic noise and BP was explored in 605 children, and the results showed that higher minimum levels of weighted day-evening-night noise and nighttime noise around the home residence may increase a child’s BP. Based on this finding, we conducted a second analysis to figure out the combined associations between air pollution and noise with BP, and found that ambient air pollution was not consistently associated with BP with adjustment for noise. Furthermore, the effects of ambient air pollution on eNO were explored within 1985 children, and we observed a significant positive association between short-term, but not long-term, air pollution with childhood eNO. In conclusion, our study provided more epidemiological evidence on the adverse health impacts of ambient air pollution and noise in school-aged children, and highlighted the confounding association between ambient air pollution and noise. More studies are needed to better assess the combined health effects of ambient air pollution and noise in children.
Frühere Studien haben über die gesundheitsschädigende Wirkung von Luftschadstoffen und Lärm berichtet. Allerdings betrachteten viele bislang publizierte Studien Erwachsene oder die ältere Bevölkerung. Kinder und im Speziellen die gesundheitlichen Auswirkungen von Lärm, sowie die gemeinsame Wirkung von Luftschadstoffen und Lärm wurden hingegen bislang nur wenig untersucht. Das ist ein Ziel der vorliegenden Promotionsschrift. Zusätzlich haben wir Gesundheitsgrößen betrachtet, die bisher wenig erforscht wurden. In unserer Studie haben wir die Assoziationen zwischen Luftschadstoffen und Lärmbelastung und Blutdruck und exhaliertem Stickstoffmonoxid (eNO) bei Kindern im Schulalter untersucht. Wir konnten dabei auf Daten von zwei großen deutschen Geburtskohorten zurückgreifen. Die Lärmbelastung innerhalb eines Umkreises von 50m um die Wohnadresse jedes Studienteilnehmers wurde anhand von Lärmpegelkarten im Geographischen Informationssystem modelliert. Schätzungen der mittleren jährlichen Konzentration von Luftschadstoffen an der jeweiligen Wohnadresse wurden anhand von „land use regression“ Modellen berechnet. Kurzzeit-Konzentrationen von Luftschadstoffen wurden mit Hilfe von Hintergrund Monitoring Stationen gesammelt. Informationen zu Blutdruck und eNO wurden während einer körperlichen Untersuchung beim Follow-up der Kohorten im Alter von 10 Jahren gemessen. Wir haben die Auswirkungen von Luftschadstoffexposition und Lärmbelastung auf die Gesundheit von Kindern unter drei verschiedenen Aspekten betrachtet. Der Zusammenhang zwischen Verkehrslärm und Blutdruck wurde bei 605 Kindern untersucht und die Ergebnisse legen nahe, dass ein höherer Mindestpegel des gewichteten Tag-Abend-Nacht Lärmes und des Lärmes während der Nachtzeit um die Wohnung den Blutdruck der Kinder erhöhen könnte. Auf Grund dieser Erkenntnis haben wir eine zweite Auswertung durchgeführt um den gemeinsamen Zusammenhang zwischen Luftschadstoffbelastung und Lärm mit Blutdruck zu untersuchen und haben festgestellt, dass die Luftschadstoffexposition nach einer Adjustierung für Lärm nicht konsistent mit Blutdruck assoziiert war. Darüber hinaus wurden die Auswirkungen der Luftverschmutzung auf das eNO bei 1985 Kindern untersucht. Dabei wurde ein signifikanter, positiver Zusammenhang zwischen Kurzzeit-, jedoch nicht zwischen Langzeitexposition mit Luftschadstoffen und eNO beobachtet. Zusammenfassend lässt sich festhalten, dass unsere Studie weitere epidemiologische Erkenntnisse über die negativen gesundheitlichen Auswirkungen von Luftverschmutzung und Lärm bei Schulkindern geliefert hat. Insbesondere wird damit betont, dass Luftschadstoffe und Lärm wechselseitige Störgrößen in Assoziationen darstellen können. Allerdings sind weitere Studien notwendig, um gesundheitliche Auswirkungen von Luftschadstoffen auf die Knochenumsatzrate bei Kindern abschließend beurteilen zu können.

Пандемія COVID-19 це інфекційне захворювання, спричинене останнім із відкритих вірусів родини коронавірусів. Спалах інфекції припав на грудень 2019 року у м.Ухань, Хубей, КНР, та визнаний ВООЗ пандемією 11 березня 2020 р.На відміну від пасажирських перевезень, вантажні авіалінії, під час пандемії, працюють з великою ефективністю. Під час карантину у всьому світі авіаперевезення вантажів є найбільш затребуваними. Зокрема, деякі українські (і не тільки) авіакомпанії переробили пару своїх літаків для перевезення вантажів. Наприклад, авіакомпанія “SkyUp Airlines”, перші вантажні рейси, здійснила в березні та квітні - вони перевозили переважно медичні витратні матеріали. Також “Міжнародні авіалінії України” вирішили здійснювати вантажні рейси з розміщенням вантажів в кабінах літаків та в багажному відділенні. Максимальна ефективність використання внутрішнього простору повітряного судна залежить від правильного пакування вантажу в контейнери певного розміру, їх розміщення та закріплення. Наприклад, за умови безкоштовної компоновки в Boeing-737 можна перевезти загалом близько 70 кубічних метрів та близько 160 кубічних метрів вантажів у Boeing-767.
The COVID-19 pandemic is an infectious disease caused by the latest virus in the coronavirus family. The outbreak occurred in December 2019 in Wuhan, Hubei, China, and was recognized by the WHO as a pandemic on March 11, 2020. In contrast to passenger traffic, cargo airlines, during pandemics, work with great efficiency. During quarantine, air freight is the most popular worldwide. In particular, some Ukrainian (and not only) airlines have redesigned a couple of their aircraft to carry cargo. For example, SkyUp Airlines, the first cargo flights, carried out in March and April - they transported mainly medical supplies. Also, Ukraine International Airlines decided to operate cargo flights with cargo in the cockpits and luggage compartment. Maximum efficiency of internal use the space of the aircraft depends on the proper packaging of cargo in containers of a certain size, their placement and securing. For example, with a free layout in the Boeing-737, you can transport a total of about 70 cubic meters and about 160 cubic meters of cargo in the Boeing-767.

1. “Proffesional English For Students Of Economic Specialization”. A. Akmaldinova (eds). K.: National Aviation University, 2017. 2. Star Alliance’s official wabpage. URL: www.staralliance.com 3. Lufthansa’s official wabpage. URL: www.lufthansa.com 4.Lufthansa’s Annual Report 2020. URL: https://investor-relations.lufthansagroup.com/fileadmin/downloads/en/financial-reports/annual-reports/LH-AR-2020-e.pdf
Nowadays we cannot imagine our life without air transportations. Transportation plays a huge role not only in everyday life, but also in the formation of the economy and gross domestic product both domestically and internationally. Air transportation is the carriage of passengers, mail, load and freight by aircraft and helicopters and all types of air transportations are classified according to the territorial sign, to objects of transportation and to direction of transportation. Air transport entered our life like no other and was able to bring dreams into reality by the safety, comfort and speed. In 2020, aviation faced problems related to the COVID-19 pandemic, which made adjustments to the plans of all airlines around the world. That is why the main goal of this work is to analyze how the pandemic influenced two of the best airline around the world – Lufthansa. У наш час ми не можемо уявити своє життя без повітряних перевезень. Транспорт відіграє величезну роль не тільки в повсякденному житті, але й у формуванні економіки та валового внутрішнього продукту як на внутрішньому, так і на міжнародному рівні. Повітряні перевезення - це перевезення пасажирів, пошти, вантажу та вантажів літаками та вертольотами, і всі види повітряних перевезень класифікуються за територіальним знаком, за об'єктами перевезення та за напрямом перевезення. Повітряний транспорт увійшов у наше життя як ніхто інший і зміг втілити мрії в життя завдяки безпеці, комфорту та швидкості. У 2020 році авіація зіткнулася з проблемами, пов’язаними з пандемією COVID-19, яка внесла корективи в плани всіх авіакомпаній світу. Ось чому основною метою цієї роботи є проаналізувати, як пандемія вплинула на дві найкращі авіакомпанії світу - Люфтганза.

Істотне зменшення авіаперевезень (як внутрішніх, так і зовнішніх), що зумовлено пандемією COVID-19 та її стрімким поширенням по всьому світу. Так, лише за січень-вересень 2020 року аеропорти України, за оперативними даними, обслужили 6,857 млн. пасажирів - це на 62,9% менше, ніж за аналогічний період 2019 року. В міжнародному сполученні пасажиропотік українських аеропортів упав на 63,7% - до 6,063 млн. осіб. При цьому, у січнівересні українські авіакомпанії обслужили майже 3,770 млн. пасажирів, що на 64,7% менше показника за аналогічний період 2019 року. За 9 місяців 2020 року українські авіакомпанії виконали 33,5 тис. комерційних рейсів (скорочення - на 58%), в тому числі міжнародних - 26,7 тис. (-60,1%)
Впродовж січня – вересня 2019 року 29 вітчизняних авіакомпаній загалом виконали 79,7 тис. комерційних рейсів, що перевищує показник аналогічного періоду минулого року на 3, 37%; пасажирів перевезено 10664,5 тис.чол, що на 10,2% перевищує аналогічний період 2018 року. Пасажирські перевезення здійснювали 18 вітчизняних авіапідприємств, серед яких традиційно лідером є авіакомпанія «Міжнародні авіалінії України» (зростання обсягів на 4,1 відсотка). Разом з цим, значні обсяги пасажирських перевезень виконано авіакомпаніями «Азур Ейр Україна» (зростання – на 48,1 відсотка), «Скайап» (зростання – у 4,3 раза) та «Роза вітрів» (зростання – на 10,8 відсотка). Також слід відмітити, що п’яту позицію зайняла авіакомпанія «Буковина», яка виконує пасажирські перевезення починаючи з листопада минулого року

The places in which we live have a direct influence on our health and wellbeing. The interest in human health and experience of a space was apparent in the work of 20th century architects such as Le-Corbusier and Alvar Aalto during the tuberculosis epidemic. The Paimio Sanatorium, which was a collaboration between doctors and architect by Alvar Aalto in 1929-33, was one of the most famous projects that shows the tuberculosis influence on architecture. Therefore, the need to redesign spaces in order to live a happier and healthier life began to influence modern architecture from the early 20th century. The change of body perception because of disease impacted architecture, reconfiguring it in a way that the building could function as a medical tool. However, after years of living in a world without pandemics, designers just about to forget the importance of the design and its influence on human health. Although, the new restrictions placed on society due to Covid-19 outbreak, played an important role to reconsider the functional connection between the built environment and human wellness. This thesis explores the ways that the built environment and its surroundings can affect human physical and mental wellbeing by examining the ways that the world has adapted to the new trends and strategies through the design of an assisted living facility in Oldtown, Alexandria, Virginia.
Master of Architecture
In the early months of 2020, the World Health Organization announced a pandemic due to Covid-19 which was first reported in China. Following the WHO declaration, people were forced to be quarantined for months. The fear of the contagious airborne disease became the most important factor in determining which spaces people can safely frequent. Therefore, space became an essential component of concern during the Covid-19 pandemic and will continue to play a role in architecture thereafter. These issues are examined through the design of an assisted living facility in Oldtown Alexandria, Virginia.

На зниження попиту на авіаперевезення вплинули проблеми зі страхом та здоров’ям, нижчим рівнем наявного доходу , відсутністю довіри споживачів при поновленні рейсів та інше. Таким чином, стан авіаційної галузі буде формуватися через політичні судження щодо вироблення національної та міжнародної економічної політики. У зв'язку з цим, авіакомпаніям необхідно стимулювати попит на перевезення.
Поряд з іншими галузями економіки, повітряний рух вразливий до зовнішніх факторів, таких як: нафтові кризи, стихійні лиха, збройні конфлікти, терористичні атаки, економічний спад та спалахи хвороб. Здається, ці зовнішні впливи мають більш серйозний і швидший вплив на кількість повітряних перевезень, оскільки раптове збільшення відміни рейсів, посадки літаків, заборон на перевезення та перекриття кордонів швидко відчувається при менших коефіцієнтах навантаження для авіакомпаній, тоді як аеропорти втрачають неповітряні доходи.

The present work reports the impacts on urban mobility and air quality in Lisbon, Portugal as a consequence of the imposed restrictions to curb the transmission of SARS-CoV-2 virus which causes COVID-19 disease. During the first national emergency period (18-03-2020 to 03-05-2020) the sharp reductions in anthropogenic activities, most importantly road traffic, resulted in generally reduced criteria air pollutant concentration when compared to a homologous baseline from 2013-2019 measured in the six air quality monitoring stations throughout the city. The most negatively impacted air pollutant was 𝑁𝑂2 with a reduction of 54.35% in traffic stations and 28.62% reduction in background stations. An exception to this trend was the observed 𝑂3 concentration increase of 12.89% in traffic stations which is potentially due to changes in the 𝑁𝑂𝑥:VOC ratio and reduced 𝑂3 titration by 𝑁𝑂 as a result of sharp decrease of 𝑁𝑂𝑥 emissions in the usually most polluted city hotspots. This phenomenon raises the need of additional measures to mitigate 𝑂3 pollution increases as part of the Lisbon and Tagus Valley air quality improvement plan which aims to reduce 𝑁𝑂2 concentrations, namely specific measures for VOC management. Google mobility indicator for local commerce was found to be the main anthropogenic activity indicator for Lisbon with a moderate and positive correlation with 𝑁𝑂2 concentration (r=+0.54), whereas the average wind speed was the most relevant natural phenomena contributing to 𝑁𝑂2 concentration with a moderate and negative correlation (r=-0.53). A regressor ML pipeline was trained to predict 𝑁𝑂2 concentration with the available anthropogenic activity, weather, and air pollutant inputs from March/2020 to March/2021, achieving 𝑅2=0.925 on the test set and subsequent feature importance analysis uncovered that anthropogenic features contribute to 41.19% of 𝑁𝑂2 concentrations and natural phenomena features contribute to 58.81%.
O presente trabalho relata os impactos na mobilidade urbana e qualidade do ar em Lisboa, Portugal, como consequência das restrições impostas para conter a transmissão do vírus SARS-CoV-2, causador da doença COVID-19, onde durante o primeiro período de emergência nacional (18-03-2020 a 03-05-2020) as reduções acentuadas nas atividades antropogénicas, nomeadamente o tráfego rodoviário, resultaram na redução generalizada das concentrações dos principais poluentes atmosféricos medidos nas seis estações de monitorização da qualidade do ar em Lisboa quando comparados ao período homólogo de 2013-2019, sendo o 𝑁𝑂2 o poluente atmosférico mais impactado com uma redução média de 54.35% nas estações de tráfego e 28.62% nas estações de fundo. Uma exceção a esta tendência foi o aumento observado na concentração de 𝑂3 de 12.89% nas estações de tráfego potencialmente devido a mudanças na relação 𝑁𝑂𝑥:COV e redução da ação de redução de 𝑂3 por reação com 𝑁𝑂 como resultado da redução acentuada da concentração de 𝑁𝑂𝑥 nas zonas habitualmente mais poluídas da cidade. Este fenómeno reforça a necessidade de medidas que mitiguem o aumento da poluição de 𝑂3 no âmbito do plano de melhoria da qualidade do ar de Lisboa e Vale do Tejo que visa a redução das concentrações de 𝑁𝑂2, nomeadamente medidas específicas de gestão de COV. O indicador de mobilidade da Google para o comércio local em Lisboa foi identificado como a atividade antropogénica mais relevante com uma correlação moderada e positiva com a concentração 𝑁𝑂2 (r=+0.54). A velocidade média do vento foi identificada como a atividade natural mais relevante com uma correlação moderada e negativa com a concentração 𝑁𝑂2 (r=-0.53). Foi treinada uma ML pipeline para prever a concentração 𝑁𝑂2 que teve como entradas os dados de atividade antropogénica, meteorológica e qualidade do ar desde Março/2020 a Março/2021, obtendo 𝑅2=0.925 no conjunto de teste. A análise de importância dos atributos identificam as variáveis antropogénicas como responsáveis por 41.19% da concentração 𝑁𝑂2 enquanto que as variáveis naturais respondem por 58.81%.

High PM2.5-related mortality and morbidity has become a public health concern in China. To date, there have been few studies investigating individual implementation and use of protective behaviors to counter outdoor PM2.5 air pollution levels in China. This study, therefore, aimed to investigate adults’ attitudes toward evidence-based protective behaviors against outdoor PM2.5 air pollution, the results of which might inform health educators and health promotion specialists about what they should emphasize when educating communities about protective behaviors in the PM2.5 air pollution days. Utilizing the purposing sampling method, a WeChat-based survey was conducted among 300 adult participants living in B residential area in Yuhuatai district of Nanjing, which is a representative city of high urbanization level and PM2.5 air pollution in China. The survey included total 16 items assessing participants’ background information, attitudes toward four evidence-based protective behaviors against PM2.5 air pollution, and knowledge regarding possibly effective protective approaches specifically related to Chinese medicine in the PM2.5 air pollution. The results showed that the importance adults in Nanjing attached to wearing N95 respirator when walking outside, putting air filter (HEPA) at home, and avoiding unprotected outdoor sports activities in the PM2.5 air pollution was greater than closing all the doors, windows, and many openings in the PM2.5 air pollution. Regarding comparison of attitudes between pre- and post-controlled COVID-19 periods, the value adults gave to closing all the doors, windows, and many openings in the PM2.5 air pollution was higher during pre-COVID-19 period, whereas the opposite of circumstance took place when referring to other three protective behaviors. Regarding comparison of attitudes between biographic variables, adults aged 18-50 (including 50) attached greater importance to all the four protective behaviors than those aged 50+. In addition, adults having the habit of checking daily AQI ranked the behaviors of avoiding outdoor sports activities and wearing N95 respirator when walking outside in the PM2.5 air pollution in a higher position than those not. Implications for future research and practice are discussed, based on a critique of the present work.

Dissertação de Mestrado em Geografia Física - Ambiente e Ordenamento do Território apresentada à Faculdade de Letras
A poluição ambiental é um tema que ultimamente é falado com frequência, devido as alterações climáticas que o Mundo tem vindo a presenciar. Muito se fala de que forma podemos tornar o Mundo sustentável para se conseguir combater este problema – não existe planeta B. Neste caso de estudo fala-se a cerca de gases poluentes que são emitidos para atmosfera com alguma frequência. A pandemia COVID-19 que nos assola praticamente há dois anos, introduziu graves problemas na saúde e na economia, causando uma forte mortalidade ao longo deste período, mas também uma crise económica a nível mundial devido a todas as restrições impostas. No caso de Portugal numa altura em que a economia tomava um rumo crescente, a pandemia veio gerar mais problemas económicos com o fecho de praticamente todo o tipo de indústria e de comércio, bem como fortes restrições à mobilidade. Porém, a pandemia trouxe também um aspeto positivo: o decréscimo significativo da poluição. Com base em imagens satélite – Ásia, Europa ou mesmo no caso português – constatou-se a diminuição poluição em muitos territórios e cidades. Este trabalho, foca-se nesta temática – alterações nos valores de poluição em diferentes momentos da evolução da pandemia -, com a tentativa de perceber se na realidade os confinamentos que foram decretados tiveram efeito na redução da poluição. Através dos dados recolhidos em duas estações da rede nacional de controle da poluição na cidade de Coimbra (centro litoral de Portugal), - Avenida Fernão de Magalhães e outro no Instituto Geofísico da Universidade de Coimbra –, em dois setores da cidade com características bastante diferentes. Ao se definirem cinco momentos que abrangeram meses e semanas, anteriores, durante e nos pós confinamentos, onde foram analisadas as evoluções ao longo da pandemia de diferentes poluentes (PM10, CO, NO, NO2 e O3), assim como a comparação da evolução dos PM10 entre as duas estações.Tem assim como objetivo analisar em vários períodos temporais (cinco), a evolução dos valores de diferentes poluentes, tendo em consideração o modo como os confinamentos tiveram efeito positivo ou negativo nos dados recolhidos, bem como mostra o peso dos diferentes estados de tempo e dos diferentes elementos climáticos na correlação dos valores registados.
Nowadays, environmental pollution is a topic of discussion, due the climate changes that the world has been witnessing. One of them is how we can make the world sustainable in order to combat this problem - there is no planet B. In this study case, there are conversations about polluting gases emitted into the atmosphere with some frequency. The COVID-19 pandemic, which has been plaguing us for almost two years, has introduced serious health and economic problems, causing high mortality over this period, also an economic crisis worldwide due to all the restrictions imposed. In the case of Portugal, at a time when the economy was taking a growing course, the pandemic generated more economic problems with the closure of practically all types of industry and commerce, as well as strong restrictions on mobility. However, the pandemic also brought a positive aspect: the significant decrease in pollution. Based on satellite images – Asia, Europe or even in the portuguese case – a decrease in pollution was observed in many territories and cities.This work focuses on this theme - changes in pollution values at different times in the evolution of the pandemic - with an attempt to understand if in reality the confinements that were enacted had an effect on reducing pollution. Through data collected at two stations of the national pollution control network in the city of Coimbra (Portugal coastal center), - Avenida Fernão de Magalhães and another at the Geophysical Institute of the University of Coimbra -, in two sectors of the city with very different characteristics. By defining five moments that covered months and weeks, before, during and after confinement, where the evolutions of different pollutants (PM10, CO, NO, NO2 and O3) were analyzed throughout the pandemic, as well as the comparison of the evolution of the PM10 between the two stations.It thus aims to analyze the evolution of the values of different pollutants in several time periods (five), taking into account the way in which the confinements had a positive or negative effect on the data collected, as well as showing the weight of the different weather conditions and the different climatic elements in the correlation of the recorded values.

The aim of this research is to evaluate how the novel Coronavirus impact on the airline industry is reflected on the affected travelers’ concerns expressed in the comments they write online. In this study, a sample of 639 comments related to the airline industry, written on the website of the Italian National Consumer Union, has been assessed through an automated sentiment analysis. The achieved results showed that travelers’ attention was directed mainly towards compensations, cancellations, and COVID-19 and at the same time they had mixed and unpredictable feelings. This suggests that consumers may understood that airline companies are facing unsustainable cash-flow and revenue situations. Moreover, all the hypotheses, grounded on the existing literature were refuted. Accordingly, we argue that the actual context prevents assessments based on previous assumptions and studies related to the impact of COVID-19 need to be conducted anew.
O objetivo deste estudo é avaliar como o impacto do novo Coronavírus no setor aéreo se reflete nas preocupações dos viajantes afetados através dos comentários que eles escrevem on-line. Neste estudo, uma amostra de 639 comentários relacionados com o setor aéreo, escritos no website da União Nacional dos Consumidores da Itália, foi avaliada através de uma análise de sentimentos automática. Os resultados alcançados mostraram que a atenção dos viajantes foi sobretudo focada nas compensações, cancelamentos e COVID-19 sendo que, ao mesmo tempo, os sentimentos revelados eram confusos e imprevisíveis. Tal sugere que os consumidores podem ter de certa maneira aceite que as empresas aéreas estão a enfrentar situações insustentáveis de tesouraria e receita. Adicionalmente, todas as hipóteses, baseadas na literatura existente, foram refutadas. Assim, argumentamos que o contexto real impedem análises baseadas em assunções anteriores, sendo que é necessário desenvolver de raiz estudos relacionados com o impacto da COVID-19.

O ano de 2020 vai ficar marcado na história pela pandemia causada pela Covid-19. O alto índice de transmissão da doença afetou a maioria das economias a nível mundial, particularmente, o setor da aviação. O receio da população em viajar acrescido às medidas de confinamento impostas por governos e ao encerramento de fronteiras, resultou num cenário temporário de aeronaves inoperacionais. Como consequência, enquanto algumas companhias aéreas decretaram falência, outras encontraram-se completamente dependentes de ajudas financeiras do Estado como forma de ultrapassar a crise que se desenhava. Todas as dificuldades enfrentadas resultaram num prejuízo estimado, a nível mundial, para o setor em cerca de aproximadamente US$ 118,5 bilhões (IATA, 2020). Tendo em conta que a atividade principal das companhias aéreas só é possível decorrer através do uso de suas aeronaves, o objetivo do presente estudo consistiu em estimar, com base na Norma Internacional de Contabilidade n.º 36 – Imparidade de ativos, a quantia recuperável destes ativos do setor da aviação comercial europeu. Para este fim, aplicou-se uma metodologia que teve em consideração uma amostra, nomeadamente os Grupos Air France-KLM, IAG, Lufthansa e Ryanair, para as quais foi aplicada a abordagem dos Fluxos de Caixa Esperados, calculando o valor presente através de uma taxa de desconto. Para este efeito, foi apurado o Custo Médio Ponderado de Capital. O presente estudo teve em consideração dois cenários distintos, sendo um mais provável, onde a recuperação do setor ocorrerá no ano de 2024, e um segundo menos provável, onde a recuperação ocorrerá em 2027. Os pressupostos considerados na presente dissertação permitiram concluir que os Grupos Lufthansa e Ryanair não indicam qualquer perda por imparidade a ser reconhecida nas contas a findar em 31.12.2021. Para o Grupo IAG, concluímos que poderá ocorrer uma reversão da perda por imparidade reconhecida em 2020. Por fim, para o Grupo Air France-KLM, verificámos a necessidade de reforçar a perda por imparidade a qual ascenderia aproximadamente a 674M€.
The year of 2020 will be marked in history by the pandemic caused by the Covid-19 outbreak. Worldwide economies and markets have been affected by the consequences of the highly transmissible disease, particularly the aviation segment. The fear of the population to travel combined with the imposed restrictions taken by the governments to contain the spread of the contamination, such as lockdowns and borders closures, have resulted in aircrafts becoming temporarily inoperable. As a result, while many airlines went bankrupted, other became dependent of State rescue loans as the only way to turnaround and survive the crisis. The estimated losses of US$ 118,5 billion (IATA, 2020) worldwide have hit the sector due to the unprecedent market turbulence. Considering that the main activity of airlines is only possible through their aircrafts, the objective of this study consists in estimating, based on International Accounting Standard n.º 36 – Impairment of Assets, the recoverable amount of these assets in the European Union commercial aviation sector. For this purpose, a methodology that took into consideration a sample was applied. This sample consists of the Air France-KLM, the IAG, the Lufthansa and the Ryanair Groups. The assumption of Expected Cash Flows was applied, these being discounted using a discount rate. For this purpose, the Weighted Average Cost of Capital has been taken into consideration. In the present study, we presumed two distinct scenarios, one being more probable, where the recovery of the sector will occur in the year 2024, and another less probable, where the recovery will occur in the year 2027. The assumptions considered in this dissertation allowed us to conclude that Lufthansa and Ryanair Groups do not indicate any impairment loss to be recognized on the reporting date of 12.31.2021. For the IAG Group, we concluded that there could be a reversal of the impairment loss recognized in 2020. Finally, for Air France-KLM Group, we verified the need to reinforce the impairment which would amount to approximately €674M.
Mestrado em Contabilidade

This equity research report looks to provide context to an equity valuation of US-based airline Delta Air Lines, Inc. (DAL:NYSE). The report goes over the past performance of the Delta and its US-based peers while providing some insights on the company's operation. Afterwards, it reflects on the current industry conditions, where the COVID-19 pandemic takes the centre stage on the analysis. Finally, the report identifies future trends for the US airline market.

Grandes impactos na demanda por transporte aéreo como a pandemia COVID-19 tendem a causar efeitos estruturais de longo prazo. A conectividade aérea das regiões Norte e Nordeste do Brasil é essencial para a integração com o resto do território brasileiro e para o desenvolvimento econômico. Estas regiões têm os menores PIB per capita do país e altos níveis de desigualdade. Os aeroportos destas regiões são predominantemente pequenos e têm baixa conectividade. Pesquisamos o impacto comparativo da pandemia em aeroportos grandes e pequenos. Para isto, adaptamos o Airport Connectivity Quality Index (ACQI) de Wittman & Swelbar (2013) e o calculamos para todos os aeroportos brasileiros com base nas etapas combinadas de rotas domésticas de passageiros no Brasil durante dois períodos: 1) Pré-COVID – 975.270 voos entre Outubro de 2019 e Março de 2020; 2) Durante o COVID – 549.357 voos entre Outubro de 2020 e Março de 2021. Encontramos maior perda de conectividade em aeroportos grandes, localizados em municípios com PIBs altos e maior população, do que em aeroportos pequenos. Durante o COVID, na Região Norte, companhias aéreas regionais e sub-regionais operando aeronaves menores em rotas menos densas introduziram novas rotas intrarregionais com impacto socioeconômico importante. A viabilidade deste modelo de negócios na Região Norte parece derivar da deficiência dos outros modais de transporte de passageiros na região. Em termos de política pública, a conectividade na Região Norte se beneficiaria de incentivos para a criação de companhias aéreas regionais e sub-regionais e de proteção de suas operações de condutas anticompetitivas.
Major impacts on the demand for air transportation such as the COVID-19 pandemic tend to have long-term structural effects. Air connectivity in the North and Northeast regions of Brazil is essential for the integration with the rest of the Brazilian territory and for economic development. These regions have the lowest per capita GDPs in the country and high levels of income inequality. The regions’ airports are predominantly small and with low connectivity. In this paper, we research the comparative impact of the pandemic on large and small airports. To accomplish this, we adapted Wittman & Swelbar's (2013) Airport Connectivity Quality Index (ACQI) and calculated it for all Brazilian airports based on combined stages of regular domestic passenger routes in Brazil during two time periods: 1) Pré-COVID - 975,270 flights between October 2019 - March 2020; and 2) During COVID - 549,357 between October 2020 - March 2021. We found that larger airports, located in places with higher GDP and population, lost more connectivity quality than smaller airports. During COVID, in the Northern Region, regional and sub-regional airlines operating smaller aircraft on less dense routes introduced new regular intra-regional routes with an important socioeconomic impact. The viability of this business model in the North Region seems to result from the deficiency of other methods of passenger transport in the region. In terms of public policy, connectivity in the Northern Region would benefit from incentives to create regional and sub-regional airlines and from protecting operations from anticompetitive conduct.

Orientação: José Manuel Ivo Carvalho Vicente ; co-orientação: Eliana Cristina Agostinho Mendes
O transporte aéreo comercial é, atualmente, um setor essencial no desenvolvimento económico pois funciona como agente facilitador nas trocas comerciais e culturais entre países e representa cerca de 35% do comércio mundial (Comunicação da Comissão 2020/C 100 I/01). Em março de 2020, a Organização Mundial de Saúde anuncia o COVID-19 como pandemia, levando a que todos os países tomassem medidas rigorosas para conter o surto pandémico. As restrições foram aplicadas pelos países sem uniformidade de critérios, contudo, na indústria do transporte aéreo a decisão foi internacional e culminou com o encerramento dos aeroportos, resultando numa grave crise económica para a aviação civil. A presente investigação tem como objetivo demonstrar a importância estratégica do transporte da carga aérea em contexto de pandemia. Este estudo trata de analisar a forma como o COVID-19 influenciou o transporte de carga aérea, designadamente, na companhia aérea Emirates na rota Lisboa-Dubai-Lisboa. Para este efeito, estabeleceu-se uma relação entre as diferentes variáveis e o problema identificado, utilizando dados estatísticos trabalhados através dos Dados de Painel e do método de Regressão dos Mínimos Quadrados Parciais (PLSR), em virtude desta metodologia ter um algoritmo robusto e de minimizar os efeitos da multicolinearidade de amostras de reduzida dimensão como as analisadas no presente estudo. Em síntese, o cenário provocado pela pandemia COVID-19 teve um impacto negativo na indústria do transporte de carga aérea. No entanto, a Emirates ajustou a sua estratégia ao contexto pandémico com o transporte de frete na cabine de passageiros, mitigando as suas perdas durante a crise COVID-19.
The commercial air transportation is currently an essential sector for the economic development as it enables commercial and cultural exchange between countries, and it represents about 35% of the world commerce (Comunicação da Comissão 2020/C 100 I/01). In March 2020, the World Health Organization announced COVID-19 as a pandemic, prompting all countries to adopt strict measures to contain the outbreak. The restrictions were applied by countries without uniformity of criteria, nevertheless, in the air transportation industry the decision was international and led to airports closure, resulting in a serious economic crisis for civil aviation. The following presentation aims to demonstrate the strategic importance of air freight transportation during a pandemic context. This study analyses the way COVID-19 has influenced Air Freight, namely in Emirates airline on the Lisbon-Dubai-Lisbon route. For this purpose, a relationship was established between the different variables and the identified issue, based on statistical data worked through the Panel Data and Partial Least Squares Regression method (PLSR), due to this methodology having a robust algorithm and minimizing multicollinearity effects in smaller samples as the ones presented in this study. In synthesis, the scenario caused by COVID-19 pandemic had a negative impact in air freight transport. However, Emirates has adjusted its strategy to the pandemic context with cargo transportation in the passenger cabin, mitigating their losses during COVID-19 crise.