Research

I educate, train students, and conduct research at UC Irvine. My teaching includes undergraduate and graduate courses on global environmental issues and solutions, and graduate seminars on climate physics and modeling. I am fascinated by the passage of energy and trace species through Earth’s climate system. My research group studies the microphysics of trace gas, aerosol, cloud, and surface interactions with Earth’s radiative, thermodynamic, and chemical budgets. We then (often) include these effects to improve climate models. Their simulations, combined with lab, field, and satellite data, help us predict and attribute features of climate and climate change. Current research includes mineral dust and carbonaceous aerosols, snow lifecycle and albedo, aerosol impacts on ocean biogeochemistry, wind-driven surface energy/mass exchange, climate-disease links, and terascale data analysis. Our aerosol, radiative transfer, and data processing models are freely available and are used by geoscience researchers world-wide.

Earth System Science: Dr. Zender’s recent climate research focuses on aerosol-climate interactions. He works to understand and predict wind erosion (including soil loss); mineral and nutrient re-distribution by dust; chemical, radiative, and health effects of dust; and the fundamental physics of natural aerosol mobilization, dispersal, and deposition; and snowpack, a sensitive and efficacious modulator of Earth’s climate. Others consider him a modeler, though he can swear like an observationalist. He wants to participate in field experiments. Invite him and see.

Computer Science: Dr. Zender’s recent computer science research focuses on efficient analysis of gridded datasets with storage-layer constraints. Mainly he works to accelerate and simplify analysis of this type of self-describing geoscience data in order to further climate research. Increasingly, ensembles of geoscience datasets are analyzed and intercompared with observations. Our group is pioneering a new paradigm called Group-Oriented Data Analysis and Distribution (GODAD) that facilitates such analysis. GODAD lets the scientific question organize the data, not the ad hoc granularity of all relevant datasets. The NCO User Guide illustrates GODAD techniques for climate data analysis.

Aerosols

We built the Dust Entrainment and Deposition (DEAD) model to simulate many aspects of the global distribution of windborne mineral dust. Aeolian deflation of dust alters air quality, radiative forcing, atmospheric chemistry, biogeochemistry, and human health over significant portions of the planet. Please contact us if you are interested in the mass distribution, size distribution, regional and seasonal cycle, optical depth, and chemical and radiative forcing of dust. We are happy to collaborate with any interested researchers on this topic. We are interested in aerosols besides dust, too! But so is everyone else these days, so we focus on naturally occuring aerosols that may have a strong anthropogenic component, e.g., sea salt, dust, biogenics. Why these aerosols? Since they have always been present, long timeseries of these aerosols are available in climate records such as ice cores. Thus we can use past records of them to learn more about the present, and visa versa. Why read dry journal articles about dust when you can see our MPEG movie?

Monographs: Freely Available Community Texts (FACTs)

Our goal is to coordinate the development, solicitation, standardization, and dissemination of Freely Available Community Texts (FACTs) suitable for education and teaching in the Earth system sciences. Each FACT is a living monograph available via the World Wide Web to students and scientists anywhere to study, modify, and improve. The license ensures authors retain recognition, copyright, and review priveleges over modifications to their original material. The project contains three existing, pilot FACTs designed to educate students and researchers about radiative forcing, aerosols, and particle size distributions. We encourage contributions of new material and FACTs from students, faculty, and researchers from the international geosciences community. Find out what happens when lecture notes metastasize…

Scientific Software

I maintain some software that might be of interest to radiative transfer, trace gas, aerosol, cloud, and climate modelers. The source for most of this is directly linked below. Contact me if you are interested in any of the other programs. First, a few utilities are required to build some of this software. makdep generates Makefile dependencies for Fortran code. Download the source code, makdep.c, compile it with cc -o makdep makdep.c, and place the resulting executable in your path before using the Makefile. My Makefiles often use pvmgetarch to determine the host OS.

Tarballs available with (sometimes minimal) documentation:

• CRM: CCM3 Column Radiation Model (used in Zender, 1999, and others)
• DEAD: Dust Entrainment and Deposition Model (documented and used in Zender et al., 2003, and others)
• IBP: Itty Bitty Processor, and IDL netCDF dataset viewer and analyzer for global GCM data
• NCO: netCDF Operators
• SNG: Fortran9X/200X string manipulation and GNU/POSIX-style getopt_long() command line processing
• SWNB2: Shortwave Narrow Band (gas parameters from HITRAN) Model for column and snowpack radiation (documented and used in Zender et al., 1997, Zender, 1999, Valero et al., 2003)

Custom-made distributions available with (sometimes minimal) documentation:

• mie: Mie scattering processor (algorithms of Wiscombe, 1979 and Bohren and Huffman, 1983; used in Zender et al., 1997, Grini et al., 2002, Zender et al., 2003, Flanner and Zender, 2005, Zender and Talamantes, 2006, Ammann et al., 2005)
• Habit Preserving Microphysical Cirrus Cloud Model (documented and used in Zender and Kiehl, 1994, Zender and Kiehl, 1997)
• Solar spectrum processor (documented in Labs and Neckel, 1968; Thekeakara and Drummond, 1971; Kurucz 1995; used in Zender et al., 1997, Zender, 1999)
• Solar geometry routines (documented in Michalsky, 1988; used in Zender et al., 1997, Zender, 1999)
• Multiple level single band two-stream radiation model (C-version of Toon et al., 1989)

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Research & Employment Opportunities

Following are the accumulated descriptions of the student, postdoctoral, professional, and technical research opportunities with our group for the past many years. Some positions are perennially open—we always welcome inquiries from passionate graduate students and post-docs. The position will state with green (actually teal) text whether it is open (i.e., inquiries are welcome). Positions that are open and funded have greentags. The source HTML code to this page contains commented-out recently-filled positions that can give you a sense of the range of opportunities within our group.

Undergraduates:

• Undergraduate Students interested in Global Climate Studies: (Solicitations welcome year-round) If you are interested in performing a summer research project or academic year independent study with our group, please contact me.
• Undergraduate Students interested in High Performance Computing: (Solicitations welcome year-round)If you are interested in performing a summer research project or academic year independent study on scientific computing with our group, please contact me. Try a project on language design or chunking optimization or suggest your own!

Graduate Students:

• Graduate Students interested in Global Climate Studies: (Solicitations welcome year-round, formal applications are to the ESS graduate program)If your research interests include the climate impacts of Aerosols, Boundary Layer Physics, Clouds, Desertification, Erosion, Microphysics, Radiative Transfer, Sea-ice, Snow, Surface Albedo, or Trace Gases, then we might find a mutually interesting research project. This (perennially-out-of-date) list will give you an idea of sample projects.

• Graduate Students interested in High Performance Scientific Computing: (Solicitations welcome year-round, formal applications are to the Computer Science graduate program)If your research interests include High Performance Computing, Geospatial Data Analysis, Language Design, or Workflow Parallelism then we might find a mutually interesting research project. This (perennially-out-of-date) list will give you an idea of sample projects.

Full Time PostDoctoral Research and/or Programming:

• Scientific Programming Specialist in Scientific Computing: PDF TXT (Posted May 5, 2014, Position Still Open!)We seek a permanent, full time programmer with enthusiasm for applying advanced computing techniques to global environmental problems. You will: Improve robustness, optimize, document, and extend features of the netCDF Operators (NCO), a scientific data analysis toolkit written in C/C++ and ANTLR. Incorporate geospatial features and parallelism into NCO. This position may also be filled on the academic track by a post-doctoral scholar, depending on their skills and interests. See the project website for more details.