Web Page of Dr. Penny Rowe

Dr. Penny Rowe

Research Scientist
NorthWest Research Associates

    Refractive indices
    Single scattering params
Educational Materials
    PENGUIN: gitHub
    PENGUIN High
Computer Code


My research interests include retrieving polar trace gas concentrations and cloud properties using measurements of downwelling infrared radiation. My work also seeks to improve our understanding of the atmosphere over the Antarctic Peninsula and Southern Ocean, using measurements made at Escudero Station, as part of the Antarctic Research Group of the Universidad de Santiago de Chile. I am also interested in bringing polar research into the undergraduate classroom using Polar ENgagement through GUided INquiry (PENGUIN) modules. My research interests also include measuring the effects of black carbon on snow in the Andes and in Antarctica, studying surface roughness on ice crystals through SEM images and molecular dynamics, and using molecular dynamics to explore a possibile role for RNA on ice in the origins of life on Earth.

Clouds and trace gases in polar regions

I study the greenhouse effects of clouds and trace gases in the Arctic and Antarctic to understand their contributions to the energy budget. My main collaborators are Von Walden, Chris Cox, Steven Neshyba, and Raul Cordero.

  • My graduate work involved infrared spectroscopy of water vapor, especially absorption between strong lines, or the water vapor continuum. This work was done as part of the South Pole Atmospheric Radiation and Cloud Lidar Experiment (SPARCLE) in 2000-2001 with Steve Warren and Von Walden.
  • This work also included retrievals of temperature and water vapor from downwelling infrared radiance spectra, which is an ongoing interest.
  • Recent work involves improving radiative transfer calculations of supercooled liquid cloud absorption and emission of infrared radiation. This improvement relies on incorporating the temperature dependence of the complex refractive indices of supercooled water.
  • My work also includes retrieving cloud properties from infrared radiation. I have investigated algorithms (such as optimal estimation) for retrieving cloud properties, including instrumental considerations such as calibration and instrument responsivity, sources of error such as biases, noise and error in knowledge of the atmospheric state, and limited spectral resolution. Microphysical cloud properties include optical depth, thermodynamic phase, and effective radius. I'm also interested in improving algorithms for cloud base-height retrieval.

Black carbon in the Chilean Andes

Black carbon is an anthropogenic pollutant that decreases the albedo of ice and snow. In the Chilean Andes, black carbon on glaciers enhances the melt rate. Because glaciers are an important source of drinking water in Chile, glacier loss is a topic of major concern. In July 2015, I will be part of a field expedition (led by Steven Neshyba, in collaboration with Steve Warren of the University of Washington and Raul Cordero of the Universidad de Santiago de Chile) to sample black carbon on snow in the Chilean Andes.

Roughening on ice crystal surfaces

Advances in scanning electron microscopy (SEM) have made it possible to monitor the growth and ablation of ice crystals on the surfaces of ice crystals at resolutions not previously possible. In collaboration with Steven Neshyba, our work has revealed horizontal corrugations, or "trans-prismatic strands", visible on SEM images of ice taken at the University of Puget Sound in collaboration with Steven Neshyba. We also examine consequences of the roughening for light-scattering properties affecting radiative flux and remote sensing.

Molecular dynamics at the ice-vapor interface

Key atmospheric properties of cirrus clouds can ultimately be traced back to molecular processes occurring at the ice-vapor interface. Many of these molecular-level processes can be studied by simulation, using the rapidly-advancing field of molecular dynamics (MD). Recent work, in collaboration with Steven Neshyba, has involved the use of MD to investigate how surface diffusivity affects atmospherically important phenomena, such as the mass accommodation coefficient, and mechanisms underlying ice surface roughness.