The chemical composition of the lowermost stratosphere exhibits both spatial and temporal variability depending upon the relative strength of (1) isentropic transport from the tropical tropopause layer (TTL), (2) diabatic descent from the midlatitude and northern midlatitude stratosphere followed by equatorward isentropic transport, and (3) diabatic ascent from the troposphere through convection...
Jessica Smith's Publications
Weinstock, E. M., et al. (2007), Quantifying the impact of the North American monsoon and deep midlatitude convection on the subtropical lowermost stratosphere using in situ measurements, J. Geophys. Res., 112, D18310, doi:10.1029/2007JD008554.
Pittman, J. V., et al. (2007), Transport in the subtropical lowermost stratosphere during the Cirrus Regional Study ofTropical Anvils and Cirrus Layers – Florida Area Cirrus Experiment, J. Geophys. Res., 112, D08304, doi:10.1029/2006JD007851.
We use in situ measurements of water vapor (H2O), ozone (O3), carbon dioxide(CO2), carbon monoxide (CO), nitric oxide (NO), and total reactive nitrogen (NOy)obtained during the CRYSTAL-FACE campaign in July 2002 to study summertimetransport in the subtropical lowermost stratosphere. We use an objective methodology todistinguish the latitudinal origin of the sampled air masses despite the...
Hanisco, T. F., et al. (2007), Observations of deep convective influence on stratospheric water vapor and its isotopic composition, Geophys. Res. Lett., 34, L04814, doi:10.1029/2006GL027899.
In situ observations of H2O and HDO in the midlatitude stratosphere are used to evaluate the role of convection in determining the stratospheric water budget. The observations show that water vapor in the overworld stratosphere (potential temperature > 380 K) is isotopically heavier than expected. Measurements in an airmass with anomalously high concentrations of water vapor show isotopic...
Measurements of the Total Water Content of Cirrus Clouds. Part I: Instrument Details and Calibration
Weinstock, E. M., et al. (2006a), Measurements of the total water content ofcirrus clouds. Part I: Instrument details and calibration, J. Atmos. OceanicTechnol., 23, 1397 – 1409, doi:10.1175/JTECH1928.1.
This paper describes an instrument designed to measure the sum of gas phase and solid phase water, or total water, in cirrus clouds, and to be mounted in a pallet in the underbelly of the NASA WB-57 research aircraft. The ice water content of cirrus is determined by subtracting water vapor measured simultaneously by the Harvard water vapor instrument on the aircraft. The total water instrument...
Hanisco, T. F., J. B. Smith, R. M. Stimpfle, D. M. Wilmouth, K. K. Perkins, J. R. Spackman, J. G. Anderson, D. Baumgardner, B. Gandrud, C. R. Webster, S. Dhaniyala, K. A. McKinney, and T. P. Bui, Quantifying the rate of heterogeneous processing in the Arctic polar vortex with in situ observations of OH. J. Geophys. Res., 107(D20), 8278, 2002, doi:10.1029/2001JD000425.
We present simultaneous in situ observations of OH, HO2, ClONO2, HCl, and particle surface area inside a polar stratospheric cloud undergoing rapid heterogeneous processing. A steady‐state analysis constrained by in situ observations is used to show that concentrations of OH calculated during a processing event are extremely sensitive to the assumptions regarding aerosol composition and...
Hanisco, T. F., J. B. Smith, R. M. Stimpfle, D. M. Wilmouth, J. G. Anderson, E. C. Richard, and T. P. Bui, In situ observations of HO2and OH obtained on the NASA ER-2 in the high-ClO conditions of the 1999/2000 Arctic polar vortex. J. Geophys. Res., 107(D20), 8283, 2002, doi:10.1029/2001JD001024.
Extensive observations of OH and HO2 obtained aboard the NASA ER‐2 inside the Arctic polar vortex during the SAGE III Ozone loss and Validation Experiment (SOLVE) provide the opportunity to identify and test interferences during the measurement of HO2 in the presence of high concentrations of ClO. In‐flight calibrations are consistent with small interferences from CH3O2 (8%) and...