Carbon Dioxide Emissions are Coming From an Unlikely Place — The Hudson
The reasons that a big city would be responsible for a lot of greenhouse gas emissions might seem obvious: There are more people, more cars, and greater power usage than in less populated areas. But a study by researchers from Queens College has found an unexpected source of methane and carbon dioxide emissions in New York: the Hudson River Estuary.
The study appears in Limnology and Oceanography and was authored by Queens College Ph.D. graduate Brian Brigham, Queens College lecturer Angel Montero, and Professors Jeffrey Bird and Gregory O’Mullan, both of Queens College and The Graduate Center.
The estuary, or tidal zone where the river meets the sea, runs from Albany downstream to New York City. Over two years of sampling along the river, the researchers found that the river is a source of methane and carbon dioxide to the atmosphere, and that these greenhouse gases (GHGs) largely come from human sources. There isn’t much research on estuaries as sources of GHGs, the authors say, so this study highlights the importance of taking a closer look at our city-side rivers. It also suggests that rethinking our wastewater and sewage systems could help curb urban GHG emissions.
In their sampling, the authors noted that the highest levels of methane were found in urban areas, namely, the state’s Capital District, around Albany, and New York City. They also found they could predict methane and carbon dioxide levels by looking at enterococci, a type of bacteria used as a wastewater bioindicator—further evidence that these GHGs were coming from human sources, likely via sewage overflow.
Because they were able to predict GHG levels by looking at things like bacteria and surface-water salinity, the authors say this research can be done without time-intensive and expensive GHG measurements. They hope this enables more estuarine GHG research in more places in the future—a critical step if we want to stem these emissions.