Skip to main content
U.S. flag

An official website of the United States government

Dot Gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Home » About » Leadership



Jennifer Mahoney is the Director of the NOAA Earth System Research Laboratories/Global Systems Laboratory (ESRL/GSL). She leads a staff of nearly 200 meteorologists, software engineers, and support staff dedicated to “making forecasts better.” GSL research provides the NOAA National Weather Service (NWS) and the public with rapidly-updating environmental models, state-of-the-art decision support tools, innovative visualization systems, and high-performance computing technology to support commerce and a weather-ready nation. GSL’s most recognizable accomplishments include NOAA’s High-Resolution Rapid Refresh high-impact weather prediction model used in NWS operations, the Science on a Sphere®, a six-foot diameter animated globe used to display Earth science datasets seen by nearly 50 million people each year, and forecast tools used in 120 NWS offices for predicting the weather and supporting impact-based weather decisions.

Jennifer holds a Master’s degree in Atmospheric Science from Colorado State University and a Bachelor of Arts Degree in Meteorology from the University of Northern Colorado. Jennifer is a member of the American Meteorological Society (AMS) and is serving on the Commission on the Weather, Water and Climate Enterprise Steering Committee as well as on the board for the AMS Committee on Environmental Information Processing Techniques.

Jennifer has served as GSL Deputy Director, the Lead for the Federal Aviation Administration’s (FAA) Quality Assessment Product Development Team, and as the Chief of GSD’s Forecast Impact and Quality Assessment Section. In 2017 and 2003, NOAA’S OAR (Oceanic and Atmospheric Research) selected Jennifer as the NOAA Research Employee of the Year for Leadership. Jennifer’s research expertise is in the areas of atmospheric science for aviation and winter weather, impact-based verification and assessment, and decision support strategies for forecast systems.

DaNa L. Carlis, Ph.D. is a meteorologist and serves as the Deputy Director at GSL since September 2020. He comes to GSL from the Weather Program Office (WPO) where he established the Earth Prediction Innovation Center (EPIC) Program. DaNa enjoys working between science, policy, and society to ensure better products and services for the American people. While spending over 18 years at NOAA, he began his career as a graduate student in NOAA’s Office of Education Educational Partnership Program (EPP). Soon after joining NOAA, DaNa was stationed in Honolulu, Hawaii for 3 years of intensive weather research, numerical model development, and dissertation writing. He’s held positions at the National Weather Service Environmental Modeling Center as a research meteorologist developing the world’s mostly widely used weather forecast model (Global Forecast System Model), as a policy advisor to NOAA’s Chief Scientist and NOAA’s Assistant Secretary of Environmental Observations and Prediction. In 2016, he wrote a children’s book titled “MIT: Meteorologist in Training.”
Melissa (Missy) Petty is performing the duties of Associate Director. Before taking on these duties Missy worked for CIRA within GSL, serving as Section Chief of GSL’s Forecast Impact and Quality Assessment Section (FIQAS). In this role, she worked closely with the National Weather Service, Federal Aviation Administration, and other organizations to advance forecast performance metrics as well as technologies for forecast verification and decision support.
BENJAMIN.Stan.2016.10.3.Candid.jpgStan Benjamin is a NOAA Senior Scientist for advanced modeling systems at GSL. He is an expert in atmospheric model development at global and regional scales, data assimilation development, and coupled model development. Before his Senior Scientist appointment Dr. Benjamin was Chief of the Earth Modeling Branch from 2014-2017, and Chief of the Assimilation and Modeling Branch from June 1991-Sept 2014.
GRANVILLE.Penny.2016.10.05.jpgPenny Granville has been GSL’s Administrative Officer since 2005. She manages the administrative staff working on Facility Access, Deemed Exports, and Property accountability. She coordinates the labs budget execution and aids in the budget formulation processes. Penny is the HR representative, processing personnel actions for Federal, CI and Contract staff. She is GSL’s Financial Management Center (FMC) serving as the focal point for all procurement and acquisitions matters monitoring all transactions such as purchase orders, credit card purchases, reimbursable agreements, travel, etc. Penny ensures GSL processes and staff are in compliance with NOAA, DOC and OAR guidelines, policies, and procedures.
ALEXANDER.Curtis.2017.11.07.IMG_0004.jpegCurtis Alexander is the Chief of the Assimilation and Verification Innovation Division and works on techniques to assimilate all types of weather observations, including radar and satellite data, into weather prediction models. These assimilation techniques are applied to regional models, but some applications are moving towards global model data assimilation.
GRELL.Georg.2017.06.09.jpgGeorg Grell is Chief of GSL’s Earth Prediction Advancement Division that works on combined suites of regional and global models to link atmospheric modeling with atmospheric chemistry, the ocean, and biosphere. This group works extensively with different community groups and has a leadership role with the community WRF-Chem model.
2019.Kraus.Mike.P1050575.jpgMichael Kraus is Chief of GSL's Evaluation and Decision Support Division. EDS develops state-of-the-art environmental forecast, decision support, visualization, and evaluation capabilities to provide scientifically robust forecast assessment tools, concepts, and analyses to support decision-making processes affected by the weather.
Scott Nahman is Chief of GSL’s Information Technology Services Division and the Senior IT Manager. He manages a multi-million-dollar budget and provides leadership and supervision to 30 technical experts in support of the world class research of GSL. Scott also serves as the Office of Atmospheric Research representative on the NOAA Federal Data Center Optimization Initiative. GSL is one of NOAA’s three sites that host research and development high-performance computing systems shared by the entire NOAA community. Scott Nahman graduated from the University of Colorado Naval ROTC program and served aboard the USS Germantown as the Electronics Material Officer and Electronic Warfare Officer. He began his NOAA career as a contractor working for the Wind Profiler Program in the Forecast Systems Laboratory as a Logistics Engineer in 1997. Scott transitioned to Federal employment in 2001 as the (IT) Facilities Manager within the Information and Technology Services branch of the Global Systems Division. During this time Scott has been responsible for the construction of 3,200 square feet of raised floor data center space, and the upgrade of an additional 4,350 square feet of IT infrastructure space at the David Skaggs Research Center in Boulder Colorado.
Govett.Mark.2019.for webpage.P1030898.jpgMark Govett is Chief of GSL's Advanced Technology Division (ATD). ATD identifies, investigates, and develops advanced technology methods, products, systems, and tools to support the NOAA Mission and NOAA research and operations. ATD’s work ensures NOAA stays on the cutting edge of technology.