With the COVID-19 pandemic changing the routines of millions of people living in big cities, many researchers expected to see a decline in air and water pollution. A new study from Maria Tzortziou and Brice Grunert, professor and post-doctoral researcher, respectively, of Earth and Atmospheric Science in the Division of Science, has found a decline in atmospheric nitrogen pollution in New York City, with nitrogen dioxide reducing by 30% compared to previous years.
Tzortziou’s new research has examined the relationship between the rapid change in human behaviors in response to the pandemic, with environmental conditions and pollution level in the Long Island Sound ecosystem, one of the most heavily urbanized coastal areas of North America.
”We wanted to assess how stay-at-home orders and the unprecedented decline in commuting and travel in the New York City metropolitan area, affected the quality of both air and water,” said Tzortziou. “Our research focuses on examining how the change in atmospheric nitrogen pollution due to COVID-19 restrictions, along with the shifts in the pattern of nitrogen-rich wastewater effluent, affects biogeochemistry and ecology of New York coastal water.“
According to research, emissions of atmospheric pollutants in New York City started decreasing dramatically in response to the pandemic.
“When we started looking at NASA satellite data from space in April and May, we found a decrease in nitrogen dioxide by 30% compared to previous years,” said Tzortziou.
The decline in atmospheric nitrogen pollution due to the pandemic has provided an opportunity to examine the relationship between air pollution and water quality.
“Now what goes into our air also impacts the other parts of the Earth System like lakes and coastal water. So, we are interested in exploring these linkages,” noted Tzortziou.
The study has applied an interdisciplinary framework that links air quality changes to water quality changes, satellite atmospheric measurements to satellite aquatic biogeochemical and ecological measurements, and model simulations to ongoing and new field observations. Through these rapid response activities, the study aims to address a gap in our understanding of the atmosphere-water exchange of pollutants and how environmental regulations, socioeconomic policy responses, and decision-making impact it.
Maria Tzortziou’s team at CCNY has participated in the joint COVID-19 Earth Observation Dashboard that NASA, as well as the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA), have created. In collaborating with post-doctoral researcher Brice Grunert at CCNY, the team has generated and contributed satellite data products relevant to water quality changes for specific urban areas, including Long Island Sound in the United States, as well as the North Adriatic Sea in Europe. The project has been funded by NASA’s Rapid Response and Novel Research in Earth Science Initiative.
“In addition to these measurements from space, new measurements were needed in the New York Coastal area to capture the changes in atmospheric and water quality conditions,” added Tzortziou. “This work has included ground-based remote sensing measurements using our Pandora Spectrometer, and this is an instrument deployed on the roof of CUNY Advanced Science Research Center (ASRC).”
With the COVID-19 restrictions having eased in New York City, Tzortziou expects the trend of decline in air pollution to change.
“We saw an increasing trend during the reopening phase, as people started going back to work, as schools started reopening, as mobility patterns started changing again,” said Tzortziou. “Data from different sources are used to examine relative impacts of changing emissions, mobility patterns, and meteorological conditions on pollution levels in the city.”
Recently, Maria Tzortziou has also collaborated with Dr. Dianne Greenfield of the CUNY Advanced Science Research Center (ASRC) and received additional funding from the National Science Foundation to expand the project. The new project will enhance our understanding of connections between societal activity and coastal ecosystems by generating additional measurements to quantify the responses of phytoplankton to COVID-19 related shifts in nutrient quality. The project will also provide City College students with training opportunities.