Physical Sciences and Mathematics Commons^™

Fifteen Years Of Hfc-134a Satellite Observations: Comparisons With Slimcat Calculations, Jeremy J. Harrison, Martyn P. Chipperfield, Christopher D. Boone, Sandip S. Dhomse, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

The phase out of anthropogenic ozone-depleting substances such as chlorofluorocarbons under the terms of the Montreal Protocol led to the development and worldwide use of hydrofluorocarbons (HFCs) in refrigeration, air conditioning, and as blowing agents and propellants. Consequently, over recent years, the atmospheric abundances of HFCs have dramatically increased. HFCs are powerful greenhouse gases and are now controlled under the terms of the 2016 Kigali Amendment to the Montreal Protocol. HFC-134a is currently the most abundant HFC in the atmosphere, breaking the 100 ppt barrier in 2018, and can be measured in the Earth's atmosphere by the satellite remote-sensing instrument …

Nrlmsis 2.0: A Whole-Atmosphere Empirical Model Of Temperature And Neutral Species Densities, J. T. Emmert, D. P. Drob, J. M. Picone, D. E. Siskind, M. Jones Jr., M. G. Mlynczak, Peter F. Bernath, X. Chu, E. Doornbos, B. Funke, L. P. Goncharenko, M. E. Hervig, M. J. Schwartz, P. E. Sheese, F. Vargas, B. P. Williams, T. Yuan

Chemistry & Biochemistry Faculty Publications

NRLMSIS® 2.0 is an empirical atmospheric model that extends from the ground to the exobase and describes the average observed behavior of temperature, eight species densities, and mass density via a parametric analytic formulation. The model inputs are location, day of year, time of day, solar activity, and geomagnetic activity. NRLMSIS 2.0 is a major, reformulated upgrade of the previous version, NRLMSISE-00. The model now couples thermospheric species densities to the entire column, via an effective mass profile that transitions each species from the fully mixed region below ~70 km altitude to the diffusively separated region above ~200 km. Other …

Observations Of Greenhouse Gas Isotopologues With Ace-Fts And Waccm, Eric Michael Buzan

Chemistry & Biochemistry Theses & Dissertations

Increases in greenhouse gas concentrations in the atmosphere are the major driver of climate change. Quantifying the sources and sinks of these gases is a major focus of research. Measuring isotopologues, or molecules that differ in isotopic composition, is one useful way of constraining the budget of a molecule as they are highly sensitive to different sources and sinks. However, measurements above the surface have been restricted to a few locations and have only reached the lower stratosphere. Satellite-based remote sensing can achieve nearly global measurement coverage, but so far no satellites have measured isotopologues.

Presented here are measurements of …

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopic Observations: 2. Using Isotopic Diagnostics To Understand The Mid And Upper Tropospheric Moist Bias In The Tropics And Subtropics, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Sandrine Bony, Jeonghoon Lee, Derek Brown, Christophe Sturm

Chemistry & Biochemistry Faculty Publications

Evaluating the representation of processes controlling tropical and subtropical tropospheric relative humidity (RH) in atmospheric general circulation models (GCMs) is crucial to assess the credibility of predicted climate changes. GCMs have long exhibited a moist bias in the tropical and subtropical mid and upper troposphere, which could be due to the mis-representation of cloud processes or of the large-scale circulation, or to excessive diffusion during water vapor transport. The goal of this study is to use observations of the water vapor isotopic ratio to understand the cause of this bias. We compare the three-dimensional distribution of the water vapor isotopic …