IGN (2021): The COVID-19 pandemic in Spain. First wave: from the first cases to the end of June 2020
Monographs from the National Atlas of Spain. New content
The COVID-19 pandemic was directly related to various environmental elements in Spain. Although it is widely accepted that humans (our mobility, the accumulation of people in urban areas, our increased longevity, the degree to which we comply with health recommendations, etc.) are the most powerful factor in the spread of the virus, it has also been proven that several atmospheric conditions served as active agents for infection. In addition, lockdown and the temporary standstill of economic activity had several positive environmental impacts, which are assessed in this chapter.
Coronavirus is more transmissible in dry environments with high pollution levels, cold temperatures (between 5°C and 11°C) and little in the way of moving air. Conversely, geographical zones with warm temperatures (above 18°C), high relative humidity (>70%), and clean, moving air (breezes, for example) are, a priori, environments less prone to infection.
During the winter months of 2020, the amount of COVID-19 cases and fatalities worldwide were higher than in the summer months. The transmission of coronavirus, from its origin in Wuhan (China) to Europe and then to North America, did not follow the typical direction of the mid-latitude winds in the atmospheric general circulation model, what confirms that humans played a decisive role in its spread. However, it did not reach Spain until the end of February/beginning of March, a few weeks later than other European territories. This may be explained by high pressure conditions in the atmosphere, caused by a tropical maritime air mass, which brought abnormally warm temperatures and high levels of sunshine that encouraged people to spend more time outdoors.
During the initial phases of the pandemic, there were more infections in the north of Spain, which has colder night-time temperatures than the southern half of the country and the Mediterranean coast. It also spread more quickly in big cities, such as Madrid and Bilbao, where air quality is poorer than in less populated areas. The contrasting temperatures in February on the maps on Average February temperature 1981-2010 and Average February temperature 2020 clearly depict these facts. In March 2020, however, the previously settled atmospheric conditions gave way to instability, frequent storms and rain. Consequently, just as the state of alarm was enacted and the population went into lockdown, the unstable atmospheric conditions and reduction in human activity combined to clean the air and reduce pollution levels. Despite this, the cooler temperatures bred more favourable conditions for the spread of the virus.
The map showing figures on solar insolation in March 2020 compared to the average in March from 1981 to 2010 shows the frequency of cloudy and overcast days registered at the start of the pandemic. From May onwards, the general rise in temperatures contributed to reducing infection and helped slow the pandemic.
Energy is an essential and strategic resource for the socio-economic development of a country. The COVID-19 pandemic altered social behaviour, especially during the initial phases of lockdown. These changes directly impacted energy production and energy consumption in Spain in line with the rest of the European Union.
Electricity production was clearly lower (between 1 and 2 million MWh/month) from mid-March to early June 2020 (lockdown) than during the same period in 2019. Electricity production in Spain is typically at its lowest level in spring. By contrast, electricity demand is higher in winter, due to the great need for heating, industrial production and the Christmas shopping season (which is simultaneous to fewer hours of sunshine), and in summer, due to the demand for air conditioning and the influx of tourists. From July 2020 onwards, electricity production was more similar to the average figures registered in 2019, yet it stayed somewhat lower throughout the year.
The geographical distribution of the year-on-year variation (2020 vs 2019) in electricity production shows some significant facts (see the map on Electricity production and year-on-year variation), e.g. the hefty impact of the pandemic on standard consumption patterns in coastal tourist areas, where energy production fell in line with the fall in demand. Variations in production were minimal in provinces with nuclear power plants. By contrast, favourable weather conditions in 2020 enabled excellent renewable energy production (water, sun and wind); hence provinces with a higher capacity for this type of energy saw their production levels increase compared to 2019.
Petroleum product consumption in Spain clearly decreased in 2020 compared to the previous year (see the graph on the Evolution in petroleum product consumption. January-September 2019-2020). It shall be noted that the Spanish economy began to gradually recover in 2016 from the double recession back in 2008-2013, and this was reflected in the performance of energy consumption indicators in the years prior to the pandemic. However, 2020 brought a sharp halt to this recovery process. The fall was particularly steep during lockdown (from March to May), and figures for 2019 were not recovered until the end of 2020 as new waves of the virus necessitated ongoing restrictions on economic activity and on the general running of Spanish society for most of the year. The sudden halt in private travel had severe outcomes on diesel and petrol consumption, especially the former, and the fall in kerosene consumption was also striking as the sharp drop in commercial flights and tourism extended beyond the spring 2020 shutdown.
The year-on-year falls in petrol, diesel and fuel-oil consumption were remarkable throughout Spain, especially in the regions that most need to transport agri-food products, like Andalusia (Andalucía) and the Region of Valencia (Comunitat Valenciana); industrial products, like the Basque Country (Euskadi/País Vasco), Castile and León (Castilla y León) and Catalonia (Catalunya/Cataluña); and goods for trade and tourism, like the Region of Madrid (Comunidad de Madrid), Catalonia (Catalunya/Cataluña), the Region of Valencia (Comunitat Valenciana), Andalusia (Andalucía) and the Canary Islands (Canarias).
The 2019-2020 year-on-year variation in natural gas consumption was unmistakable in the regions that consume the most, i.e. Catalonia (Catalunya/Cataluña), Andalusia (Andalucía), the Region of Valencia (Comunitat Valenciana), the Basque Country (Euskadi/País Vasco) and the Region of Murcia. The decrease, as for petrol, was particularly evident during lockdown (from March to May 2020).
Greenhouse gas emissions
One of the effects of the restrictions on mobility and on economic activity during spring 2020 was the temporary reduction in greenhouse gas (GHG) emissions recorded worldwide. The Ministry for the Ecological Transition and the Demographic Challenge (2021) estimated gross emissions of 271.5 million tonnes of CO2 equivalent (CO2-eq) for 2020 in the Progress of the Greenhouse Gas Emission Inventory (Avance del Inventario de Emisiones de Gases de Efecto Invernadero), an overall 13.7% drop compared to 2019. Furthermore, total emissions were 6.4% lower than in 1990 and 38.6% lower than in 2005. This was the first time in the series (1990-2020) that emissions dipped below the figure for 1990. The graph on the Evolution in greenhouse gas emissions by sector shows the steady decline in emissions from 2000 to 2020 in several sectors, with three distinct turning points in 2008, 2013 and 2020, simultaneous to three economic downturns. Absorptions from the land-use sector, forestry and changes of use were estimated at 36.6 million tonnes of CO2-eq (13.5% of the total gross emissions in the Inventory for 2020) and must be deducted from the gross amount. Therefore, net emissions in 2020 were estimated at 234.9 million tonnes of CO2-eq, i.e. a drop of 15.2% compared to 2019.
The graph on the Monthly variation in greenhouse gas emissions using data from the Basque Centre for Climate Change (BC3) shows a drop in all months of the year for the 2019-2020 period. This drop was primarily due to the lessened activity of coal-fired power stations during the first few months. However, the most significant emission reductions were registered in the months when the most stringent lockdown was in force [April (-31%) and May (-22%)]. From the end of lockdown, in June, to September, the drop in emissions was less significant. On the graph depicting the evolution of emissions (2018-2020) by category (energy sources), the sharpest drop may be observed in petroleum and electricity, the latter having steadily reduced since 2018. The drop in emissions from electricity use may also be observed on the specific graph for this source. Emissions from coal use have been steadily decreasing since 2018, whilst emissions related to gas have hardly changed.
The reduction in greenhouse gas emissions registered in 2020 shall be regarded as an exception; it had a transient and minor impact on the overall levels of greenhouse gases in the atmosphere and, therefore, on global climate. Given that what really matters from a global perspective is the cumulative effect of greenhouse gases in the atmosphere, the impact of a temporary reduction, such as the one registered during lockdown, is negligible. In fact, a detailed analysis of historical emission trends shows that emissions would have reduced even without COVID-19. Specifically, the study carried out by the Spanish Observatory of the Energy Transition and Climate Action (OTEA, 2020) found that whilst 71% of the reduction registered in 2020 may be attributed to the pandemic, the remaining 29% would have been achieved by simply keeping the decreasing trend recorded in recent years.
Lastly, according to data from the World Meteorological Organisation (WMO), despite the pattern of decreasing emissions and the short-term effect of lockdown, carbon dioxide concentrations in the atmosphere continued to rise in 2020, exceeding the threshold of 410 parts per million. Therefore, measures to reduce emissions in a more expedient, planned and sustained way are urgently required to keep the global temperature increase below 1.5ºC.
Air quality in Europe
Lockdown and restrictions on mobility slowed down economic activity during the first wave of the COVID-19 pandemic and led to a significant drop in road transport, as outlined in other chapters. To analyse the effects of this slowdown on air pollution, the European Environment Agency (EEA) monitored the average weekly and monthly concentrations of nitrogen dioxide (NO2) and fine particles (PM 10 and PM 2.5), measured every hour or every day by nearly 3,000 gauging stations (EEA, 2020 and 2021). Exposure to air pollution may have adverse effects on health, and in particular people with respiratory diseases could be more vulnerable to COVID-19. Although the epidemiological research carried out to date is as yet inconclusive, all signs suggest that such exposure worsens the condition of people infected with coronavirus. What has been concluded is that a higher air quality prevented 2,190 early deaths in Europe ascribable to fine particles (PM 2.5) from 21 February to 17 May 2020 (Giani et al., 2020).
Data show that concentrations of NO2, which are primarily bred by road transport, decreased during lockdown. However, they do not suggest a consistent reduction in the concentration of PM 2.5 particles, probably due to the different origins of this pollutant, which include fuel for heating, industrial activity, traffic and reactions with other atmospheric pollutants, such as ammonia, which is related to the use of agricultural fertilisers. Weather conditions may also contribute to decreases or increases in the concentration of pollutants and explain, in part, why reductions in air pollution are rarely homogeneous.
The graphs show the evolution of atmospheric NO2 pollution in ten European cities between weeks 11 and 27 in 2019 and 2020. In most cases, there was a significant reduction in micrograms per cubic metre (μg / m3), which was especially remarkable in cities such as Paris (weeks 13 and 16), Milan/Milano (week 13) and Madrid (week 15).
The World Health Organisation regards noise pollution as the second most dangerous environmental risk for the population, after air pollution. Specifically, the European Environment Agency (EEA) estimates that 20% of the European population is exposed to levels of long-term noise pollution (threshold of 55 dB during the day and 45 dB at night) that endanger their health by leading to hearing loss, mental health issues and a reduced quality of life.
The spread of coronavirus was linked to air pollution, as mentioned above, but also to noise pollution, which raises stress levels and weakens the immune system. Thus, according to hospital and intensive care unit admission rates, the incidence of coronavirus infection and the severity of its symptoms are directly related to environmental noise levels. However, environmental noise does not influence mortality (Díaz et al., 2021).
During the weeks under lockdown and mobility restrictions in March, April and May 2020, there was a significant fall in noise pollution from road, air and maritime traffic (including underwater noise) and from leisure activities in public spaces. In addition to the policies undertaken by local authorities, it is worth highlighting initiatives kickstarted by many volunteers, such as Smart Citizen in Spain or Silent Cities in various countries around the world, which yielded some interesting results –although they shall be understood as an approximation–. These initiatives enabled setting minimum ground noise levels.
Graphs based on open data provided by Madrid City Council, show daily noise reductions (1 April 2019 and 2020) of up to 14% at some gauging stations, such as Méndez Álvaro, Avenida de Moratalaz, Plaza del Carmen and Urbanización Embajada. These same data show variations of up to 10 dB from March to May 2019 and 2020, which, given that dBs are expressed on a logarithmic scale, translates to a significant drop in sound pressure. Similar results were recorded at the three gauging stations taken as an example for high (Glorieta de Carlos V), medium (Paseo de la Castellana) and low (Casa de Campo) noise pollution figures.
In Barcelona, data from the City Council used for the graph on Noise levels in Barcelona during the first wave of the pandemic show minimum figures registered at the beginning of the state of alarm in gauging stations with heavy, moderate an light traffic (between 65-50 dB). These figures show a significant decrease from the equivalent average figures for 2019 (70-56 dB) and the virtual disappearance of noise pollution. However, noise pollution increased on data for 2020 with the return to work during phases 0, 1 and 2 of the downscaling process, with some exceptions at light traffic gauging stations. It is important to note that the figures recorded at the start of phase 2 were close to the baseline figures for 2019, especially in areas with heavy traffic, which means reductions were temporary. The graph on the Noise levels due to nightlife in Barcelona during the first wave of the pandemic shows how noise pollution from nightlife fell from over 60 dB, recorded for the March-June 2019 period, to 50 dB on most streets (pedestrian streets with nightlife venues, streets with traffic and nightlife venues and streets with bar terraces and people gathering) during the state of alarm, the return to work and the subsequent phases. A rapid increase in noise levels (55-57 dB) was, however, detected on streets with bar terraces during phases 1 and 2 of the downscaling process.
Finally, the drop in economic activity and transport led to a reduction in the seismic noise made by the vibrations of the earth’s crust. This reduction eased detecting and monitoring lower intensity earthquakes and volcanic activity, amongst other seismic events, as shown in the examples for Granada and Lorca (Region of Murcia/Región de Murcia).
The accelerometer records show that the average daily cultural seismic noise level drops by several decibels at the weekend. They also confirm alterations in seismic noise due to the decrease, cessation and resumption of human activities during lockdown and subsequent downscaling phases. Thus, the daily average noise level decreased during lockdown by between 1 and 7 dB, depending on the gauging station, compared to the prior reference level. Subsequently, with the gradual resumption of activity during the transition to ‘new normal life’, the cultural seismic noise progressively increased until it reached figures similar to those registered before lockdown, as shown by the daily average anthropic seismic noise levels recorded by the accelerometers in Granada and Lorca (Region of Murcia/Región de Murcia).
Wastewater pollution and water consumption
Amongst the activities deemed as being essential by the regulations passed during the state of alarm, were those involving water processing and water supply. Specifically, the Order on essential water services (Order SND/274/2020 of 22 March), adopting measures concerning water for human consumption and wastewater processing, set that the organisations responsible for water processing were providing an essential service and, as such, must be able to source the products and materials necessary to carry out their work with guarantees and in compliance with current health regulations. Also, Royal Decree Law 11/2020 considered that water supply must be guaranteed whilst the state of alarm was in force, and could only be withheld from individuals in their usual residence for supply security reasons (AEOPAS, 2021).
Beyond the supplying and processing guarantees, the Ministry for the Ecological Transition and the Demographic Challenge, together with the Ministry of Health, followed the recommendations from the European Union on the systematic surveillance of SARS-CoV-2 (EU, 2021) by launching an early-warning system based on monitoring the virus in urban wastewater (VATar COVID-19). As a result, traces of the genetic material of the virus in urban wastewater were detected and could be linked to COVID-19 cases. For this reason, the presence of coronavirus in wastewater is regarded as an early epidemiological indicator that may help anticipate, detect and monitor the spread of the disease and any possible spikes in incidence, alongside the traditional monitoring of patients with COVID-19. This coronavirus monitoring task involves analysing data from wastewater processing plants in all Spanish river basin districts, prioritising those containing effluents from hospitals, tourist areas and airports. The reclaimed water used in municipalities with insufficient processing and stretches of rivers, lakes and reservoirs used for bathing were also analysed to study the possible effects of the virus in these types of waters (Ministry for the Ecological Transition and the Demographic Challenge, 2021).
The presence of coronavirus in wastewater was first confirmed in the week starting on 19 July 2020, as shown on the map on the Trends in wastewater pollution by SARS-CoV-2. Results are quantified as genomic copies of SARS-CoV-2 per litre (cg/l) and then transformed to a logarithmic scale (log10 cg/l). For twelve weeks after this date (until 10 October 2020), there were significant weekly increases in the presence of the virus in wastewater in all cities (over +1 logarithmic unit), although the timing of the peaks differs. The peaks in Barcelona (weeks 8 and 11), Valladolid (weeks 5 and 9) and Oviedo (weeks 4 and 9) are remarkable. Interestingly, however, the results from Málaga did not register an increase of the virus in its wastewater until week 10. It is important to note that the Ministries responsible warn that point-in-time data are subject to variations in environmental conditions or changes in sampling times and shall, therefore, be taken into consideration with some caution. However, it is relevant to look at how the weekly trends correlate with the evolution of the health situation.
Data on water consumption during lockdown and the subsequent downscaling phases are also interesting. These figures show the decline in economic activity in line with data on electricity, petrol, diesel and natural gas consumption. The graphs show the evolution of water consumption by households and by the industry in the city of Seville (Sevilla) from January to July 2019 and 2020, as per the data provided by Seville Metropolitan Water Supply and Sanitation Company (EMASESA). Figures show that water consumption by households rose slightly from February 2020 and peaked at 2,700,000 m3 in March, simultaneous to the state of alarm and lockdown. Conversely, there was a significant drop in industrial consumption, which fell by 40% in April and May 2020. The data on hourly water consumption by households reveal no differences in the breakdown by daytime and night-time, whereas some changes related to different day and night-time tariffs may be detected in figures on water consumption by the industry.
The daily variation in the water supplied in Seville (Sevilla) during the first wave of the pandemic (comparing 14 March-28 June 2020 and 2019), expressed in cubic decametres (dam3) and contrasted three months after the consumption was recorded, shows increases throughout the series. The only exception was 18-20 April 2020, which was simultaneous to Easter and, therefore, was affected by public religious events being cancelled and therefore by a lower amount of tourists visiting the city (-14 dam3). Similarly, significant decreases were registered from 9 to 12 May, simultaneous to another bank holiday that usually attracts large numbers of tourists, i.e. ‘Seville April Fair’. The trend in this variation began to decrease when phase 2 of the downscaling process came into force and mobility restrictions were loosen up, with the minimum variation registered on 21 June, when the state of alarm ended. The hourly breakdown of data on water supply also identified a significant drop at 20:00 hours, simultaneous to the spontaneous and systematic applause for healthcare workers that took place throughout Spain during lockdown.
Vegetation in the city of Seville during the first wave of the pandemic
The relative increase in vegetation in part of the Metropolitan Area of Seville (Sevilla) during spring 2020 is clearly visible on the map and its relation to lockdown seems clear. Vegetation health and coverage was quantified by calculating the EVI2 vegetation index for the complete series of Sentinel-2 satellite images (A and B). Differences were calculated by comparing the average from images taken every 5 days in spring 2020 with those captured in spring 2017, 2018 and 2019. Sixty-seven Sentinel-2 images from 30STG tile at a spatial resolution of 10 m were processed. These images were then downloaded from the Sentinel Science Hub at processing levels 1-C and 2-A. The images at level 1-C, primarily for 2017 and 2018, were preprocessed using the Sen2cor atmospheric correction module, and all pixels not corresponding to land surface were masked, removing clouds, shadows and water bodies before calculating the EVI2.
The image shows green colours in most of the interstices of the city’s urban fabric. In other words, lockdown led to a positive vegetation index balance compared to the average of the three previous years. Its effect is striking on large unpaved urban open spaces where intense green colours stand out. A good example is the sandy area mainly used for parking on the left-hand sector of the image (Vega de Triana), where cancelling ‘Seville April Fair’ during the months of April and May 2020 led to an intense growth of vegetation during lockdown, an effect that may also be observed on the fairground arena itself. The lighter green colours linked to the parks in the city and the predominance of forest and herbal vegetation (Parque de María Luisa and Parque de los Príncipes) show figures close to the average, what confirms that the extraordinary growth of vegetation in streets and unpaved open spaces was a result of lockdown, rather than natural causes.
Co-authorship of the text in Spanish: Samuel Biener Camacho, Manuel Gilibert Valdés, Javier Martí Talavera, Enrique Moltó Mantero, José Ojeda Zújar, Jorge Olcina Cantos, Antonio Oliva Cañizares, Pilar Paneque Salgado, Víctor Rodríguez Galiano and Esther Sánchez Almodóvar. See the list of members engaged
Adaptation of the text and translation into English for this international version: Andrés Arístegui Cortijo (Translator in chief)
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