An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Tower based measurement network design for the North East Corridor project
Published
Author(s)
Israel Lopez Coto, Subhomoy Ghosh, Kuldeep R. Prasad, James R. Whetstone
Abstract
The North-East Corridor project aims to use a top-down inversion method to quantify sources of Greenhouse Gas (GHG) emissions in the urban areas of, in the first phase, Washington DC and Baltimore at approximately 1km2 resolutions. Since inversion methods depend on atmospheric observations of GHG, high resolution simulations along with clustering analysis were used to design a network of surface stations for the area of Washington DC/Baltimore. Thereafter, a Kalman filter within an OSSE was employed to evaluate the performances of different networks consisting of different number of towers and where the location of these towers varied. Additionally, we explored the possibility of using a very high density network of low-cost, low-accuracy sensors characterized by larger uncertainties and drift over time. Results show that too compact networks lose spatial coverage whilst too spread networks lose capabilities of constraining uncertainties in the fluxes. By using 12 towers, the spin up time of the filter is in the order of 100 h, 20 days if we use just 5 h during the afternoon hours. However, the convergence to the true values is faster with a large number of towers, reducing the response time of the filter. Larger uncertainties in the observations implies lower values of uncertainty reduction. On the other hand, the drift is a BIAS in nature, which is added to the observations and, therefore, biasing the retrieved fluxes.
Lopez, I.
, Ghosh, S.
, Prasad, K.
and Whetstone, J.
(2017),
Tower based measurement network design for the North East Corridor project, Atmospheric Environment, [online], https://doi.org/10.1007/s00376-017-6094-6
(Accessed December 15, 2024)