What is BEACO₂N?

BEACO2N is a new approach to observing atmospheric gases over an urban area. Instead of using a small number of extremely sensitive instruments to measure a large area, we blanket interesting locations with a high density network of instruments, with each instrument representing a network “node”. Individually, measurements from these nodes are of moderate quality, but when taken together as a network produce an accurate, highly resolved picture of real-time pollutant concentrations. Each node measures CO2, a major anthropogenic (human-influenced) contributor to climate change, and reports back to this site where the collected data including temperature, pressure, and relative humidity is publicly available for viewing and download. The nodes also collect data on particulate matter, nitrogen oxides, ozone, and carbon monoxide which are indicators for the overall air quality of an area, and may be useful for tracing the origins of CO2 emissions. CO2, CO, and aerosol data are available for download via this site. Data for other species is not yet ready for public viewing, but will be added to the site soon.

BEACO2N is also a novel approach to scientific outreach. A science curriculum for K-12 teachers using the BEACO2N sensors has been developed by scientists and educators at the Chabot Space and Science Center in Oakland, California. To the extent possible, nodes are being placed on the rooftops of local area schools, so that students may see for themselves the greenhouse gas (GHG) pollution in their area. We also have plans to place nodes on other local science museums, and will be working with staff to facilitate displays of the BEACO2N data.

The BEACO₂N Instrumentation

Each BEACO2N site hosts a single "node" for the network. These nodes contain sensors for CO2, NO, NO2, O3, CO, and aerosol in addition to sensors for temperature, pressure, and relative humidity. Data from these sensors are collected once every five seconds onto a miniature computer which then sends the data to a centralized server. When combined with data from other nodes, it can be used to produce concentration maps, track pollution plumes, and to constrain calculations of emissions, to name a few possibilities. The data are also stored on-board the nodes; in the event of network failure, each node will store its collected data until connectivity is restored.

Physically a BEACO2N node is about the size of a loaf of bread or shoebox. The entire device is contained in an aluminum box designed for the outdoors, weighs approximately 8 pounds, and is powered using a standard 3-prong outlet. In addition to the sensors and computer, each node contains a power converter; to prevent surges, intake and exhaust fans; to maintain an even airflow and prevent overheating, and a wi-fi connection or ethernet cable; to send data to our server on campus.

When deployed, the nodes are placed on rooftops, mounted on poles or railing that raise the instruments several feet above the roof surface. Care is taken to ensure that the nodes are placed where they will sample free flowing air away from air handling units or building exhaust. In areas where theft or vandalism is a concern, the instruments are secured according to the advice of the building managers.

If you're interested in locating a BEACO2N node on your rooftop or if you know of a good candidate site, please feel free to download and share our BEACO2N Quick Facts sheet or our informational pamphlet.