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Accurate flow measurements at the exhaust systems of large fire test facilities are critical for achieving accurate measurements of heat release rate. A detailed characterization of exhaust flow for the National Fire Research Laboratory (NFRL) has been
Anna Karion, Michael Link, Rileigh Robertson, Tyler Boyle, Dustin Poppendieck
Recent measurements of emissions of methane from residential natural gas appliances have indicated non-negligible emissions within residences, with impacts on both indoor air quality and climate. As a result, methane losses from residential buildings have
Ge Ren, Kailun Du, Shiqi Zhao, Anna Karion, Israel Lopez Coto, Xiaoning Wang, James Whetstone, Hong Lin
With China's proposed carbon reduction goals, many carbon monitoring pilot city projects have been launched, involving greenhouse gas (GHG) estimation inversion analysis based on GHG observations. For the evaluation of emissions estimates in a targeted
Dual optical frequency comb spectroscopy allows for high speed, broadband measurements without any moving parts. Here, we combine differential chirp down conversion to probe large spectral bandwidths in the near-infrared (NIR) and serrodyne modulation to
Joseph R. Pitt, Israel Lopez Coto, Anna Karion, Kristian D. Hajny, Jay M. Tomlin, Robert Kaeser, Thilina Jayarathne, Brian H. Stirm, Cody R. Floerchinger, Christopher P. Loughner, Roisin Commane, Conor K. Gately, Lucy R. Hutyra, Kevin R. Gurney, Geoffrey S. Roest, Jianming Liang, Sharon Gourdji, Kimberly Mueller, James Whetstone, Paul B. Shepson
Recent studies have shown that methane emissions are underestimated by inventories in many US urban areas. This has important implications for climate change mitigation policy at the city, state, and national levels. Uncertainty in both the spatial
Anna Karion, Paul Shepson, Thomas Butcher, Roisin Commane, Julianne M Fernandez, Tom Ferrara, Kristian Hajny, Robert Jackson, Brian Lamb, Israel Lopez Coto, Zeyneb Magavi, Brian McDonald, Zachary Merrin, Scot Miller, Kimberly Mueller, Lee Murray, Joseph Pitt, Rick Trieste, Rebecca Trojanowski, Joseph von Fischer
A workshop was held at the EDF offices in Washington, DC, on June 15 and 16, 2022, to discuss the current state of knowledge and to define productive courses of action in better determination and source apportionment of methane emission rates, and
Austin Hope, Israel Lopez Coto, Kristian Hajny, Jay M Tomlin, Robert Kaeser, Brian Stirm, Anna Karion, James Whetstone, Paul Shepson
We conduct WRF simulations at multiple resolutions down to the "grey zone" (9 km, 3 km, 1 km, 333 m) to examine boundary layer turbulence in three planetary boundary layer (PBL) schemes: the well-established MYNN PBL scheme and the two newest PBL schemes
Brendan Carter, Jonathan Sharp, Andrew Dickson, Marta Alvarez, Michael Fong, Maribel Garcia-Ibanez, Ryan Woosley, Takeshita Yuichiro, Leticia Barbero, Robert Byrne, Wei-Jun Cai, Melissa Chierici, Simon Clegg, Regina Easley, Andrea Fassbender, Kalla Fleger, Xinyu Li, Macarena Martin-Mayor, Katelyn Schockman, Aleck Wang Zhaohui
The ocean carbonate system is critical to monitor because it plays a major role in regulating Earth's climate and marine ecosystems. It is monitored using a variety of measurements, and it is commonly understood that all major components of the seawater
GAR WING TRUONG, Lukas W. Perner, D. Michelle Bailey, G Winkler, S Catano-Lopez, V Wittwer, T Sudmeyer, C Nguyen, David Follman, Adam Fleisher, OLIVER HECKL, Garrett Cole
Jay M. Tomlin, Israel Lopez Coto, Kristian D. Hajny, Joseph R. Pitt, Robert Kaeser, Brian H. Stirm, Thilina Jayarathne, Cody R. Floerchinger, Roisin Commane, Paul B. Shepson
To effectively address the unprecedented acceleration of climate change, cities across the U.S. are leading efforts to reduce greenhouse gas emissions. Coherent, aggressive, and lasting mitigation policies in controlling carbon emissions are beginning to
Eugene Song, Kang B. Lee, Nishi Hiroaki, Yuki Takayama, Janaka Wijekoon
It is vital to establish a suitable thermal environment for crop cultivation and greenhouse to improve production quality. However, in greenhouse environments, uneven temperature, caused by the influence of outside temperature, leads to unevenness in air
Anna Karion, Subhomoy Ghosh, Israel Lopez Coto, Kimberly Mueller, Sharon Gourdji, Joseph Pitt, James Whetstone
Urban methane emissions have been found to exceed estimates derived using traditional inventory methods in several US cities. In large northeastern US cities, including in Washington, DC and Baltimore, Maryland, studies using atmospheric methane
Exhaust flow measurements are a significant source of uncertainty for measurements of heat release rate in large-scale fire experiments. Irregular flow distributions are often present in the exhaust ducts, making it difficult to measure flow accurately
Many manufacturers are striving to reduce the negative impacts of their business activities, particularly with respect to greenhouse gas (GHG) emissions, also called "carbon emissions." Estimates of such emissions are ubiquitously used in evaluating
Ryan Cole, Connor Fredrick, Newton Nguyen, Scott Diddams
We report precision atmospheric spectroscopy of CO2 using a laser heterodyne radiometer (LHR) calibrated with an optical frequency comb. Using the comb-calibrated LHR, we record spectra of atmospheric CO2 near 1572.33 nm with a spectral resolution of 200
Fabrizio Giorgetta, Esther Baumann, Brian Washburn, Nathan Malarich, Jean-Daniel Deschenes, Ian Coddington, Nathan Newbury, Kevin Cossel
Greenhouse-gas dual-comb spectroscopy is extended to a city-scale 14.5-km path length using remote receiver and data acquisition. This configuration enables lower link losses and longer path lengths compared to folded paths with a remote retroreflector
We present a new fiber-amplifier-based differential absorption light detection and ranging (DIAL) system for range-resolved detection of carbon dioxide (CO2) and water vapor (H2O) over a range of a few kilometers. The fiber amplifier chain is seeded with a
Iosif Isaakovich Shinder, Aaron Johnson, James Filla, Vladimir B. Khromchenko, Michael R. Moldover, Joey Boyd, John D. Wright, John R. Stoup
We present protocols for making fast, accurate, 3-D velocity measurements in the stacks of coal-fired power plants. The measurements are traceable to internationally-recognized standards; therefore, they provide a rigorous basis for measuring and/or
Kristian D. Hajny, Joseph Rudek, David Lyon, Austin Armstrong, Cody R. Floerchinger, Thilina Jayarathne, Robert Kaeser, Tegan Lavoie, Olivia E. Salmon, Brian H. Stirm, Andrew A. Stuff, Jay M. Tomlin, Bernard Wulle, Israel Lopez Coto, Paul B. Shepson
Fabrizio Giorgetta, Esther Baumann, Brian Washburn, Nathan Malarich, J.-D. Deschenes, Ian Coddington, Nathan Newbury, Kevin Cossel
We present dual-comb spectroscopy across a 14.5-km path using remote receiver and data acquisition. This configuration results in lower link losses compared to open-path configurations with co-located transmitter and receiver.
Rodney Bryant, Artur A. Chernovsky, Joseph A. Falco, Iosif Isaakovich Shinder
This report summarizes the design and description for an automated system of velocity traverse probes. Performance of key components of the system are also described. The system is designed for conducting detailed characterizations of flow distributions in
Jocelyn Turnbull, Philip DeCola, Kimberly Mueller, Felix Vogel, Anna Karion, Israel Lopez Coto, James Whetstone
The Integrated Global Greenhouse Gas Information System (IG3IS) aims to coordinate an integrated global greenhouse gas information system, linking inventory and process model-based information with atmospheric observations and atmospheric modelling, to
Continuous wave optical parametric oscillation (OPO) provides a flexible approach for accessing mid-infrared wavelengths between 2 μm to 5 μm, but has not yet been integrated into silicon nanophotonics. Typically, Kerr OPO uses a single transverse mode