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Home » Who We Are » Organization » Leadership

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.

Curtis Alexander is the Deputy Director of GSL. Dr. Curtis Alexander (NOAA/OAR/GSL) received his undergraduate and graduate degrees from The Pennsylvania State University (1999) and the University of Oklahoma (2002, 2010) respectively. His graduate work focused on studying severe convective storms, including tornadoes, using high-resolution mobile Doppler weather radar observations. He joined the Global Systems Division (now Laboratory — GSL) of NOAA/ESRL in 2009, first as a University of Colorado CIRES employee before becoming a NOAA federal employee in 2016. He focused his research in NOAA on the development of high-resolution model systems to support convection-allowing model forecasts including data assimilation of storm-to-mesoscale information and became a division chief for the now Assimilation and Verification Innovation Division of GSL in 2017. He has helped transition multiple versions of the Rapid Refresh (RAP) and High-Resolution Rapid Refresh (HRRR) from research to operations at NWS/NCEP between 2014 and 2020 and is also a co-lead on the Unified Forecast System Short-Range Weather/Convection Allowing Model Application Team.

Melissa (Missy) Petty serves as the Associate Director for Administration in the Global Systems Laboratory (GSL). Before joining GSL’s Office of the Director, Missy worked for the Cooperative Institute for Research in the Atmosphere (CIRA) as a GSL affiliate, serving as 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 stakeholders to advance operationally-relevant forecast evaluation techniques and technologies, leading a multidisciplinary team of scientists and software engineers to perform formal, in-depth product assessments and develop related evaluation tools and decision support systems.Missy’s career began as a software engineer at the National Center for Atmospheric Research, where she was involved in the implementation of various forecast systems, including aviation weather forecasts for turbulence and ceiling and visibility, and a statistical forecast system that is used in multiple market segments. This was followed by a period in the private sector working for SAP, one of the market leaders in enterprise application software. She returned to the atmospheric science community as a software engineer in FIQAS, developing automated data processing and analysis systems to support forecast verification. Missy holds a Ph.D. in Mathematics from the University of Colorado, Boulder, and a B.A. in Mathematics from Millsaps College in Jackson, MS.

Penny 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

Ligia Bernardet is the Chief of the Earth Prediction Advancement Division (EPAD), which works to improve, test, and apply numerical weather prediction models in scales ranging from local to global and from a few hours to seasonal. EPAD’s foci of development are coupled Earth system models and atmospheric physics/composition. Ligia got her Ph.D. at Colorado State University in 1997 in numerical prediction of mesoscale convective systems. In 1999, she took a position in the National Weather Service of her native country, Brazil, to help stand up the first operational numerical weather prediction system focused on South America. In 2003 she started working at GSL (then FSL) in model testing and evaluation activities for the Developmental Testbed Center (DTC), of which she was the Deputy Director until 2022. During 2020-2022 she was EPAD’s deputy chief.

Ligia has been continuously interested in the interface between research and operations in numerical weather prediction, and has worked to bring those communities together. She has focused on modeling infrastructure projects, such as making NOAA models easier to use by the research community. More recently, she has co-led the development of the Common Community Physics Package (CCPP) to facilitate research, development, and operational use of physical parameterizations. She has also been involved in assessments of innovations for transition to the operational Unified Forecast System (UFS).

Daniel Nietfeld is Chief of the Weather Informatics and Decision Support (WIDS) Division. WIDS develops state-of-the-art environmental forecast, warning, decision support, and visualization capabilities to provide scientifically robust forecast tools, concepts, and analyses that support decision-making processes affected by the weather, water, and climate. We do this by coupling the latest advancements in machine learning, data visualization, social science research, and computer science/engineering with cutting-edge atmospheric and environmental science to empower forecasters and decision-makers with the best information they need. Our partners and customers are made up of numerous federal, state, and local government agencies that deal with operational weather and environmental issues; this includes the National Weather Service (NWS), the Federal and local Land Agencies that deal with wildfires, the Department of Defense, the Department of Transportation, the emergency management community, and international partners such as Australia and Taiwan. Through a partnership with NOAA's Office of Education and the Science on a Sphere (SOS) Team, we help NOAA communicate its science and develop new ways of interacting with our data. In addition, the WIDS Division hosts the NOAA Fire Weather Testbed, which leverages social science and verification expertise to enable research to operations (R2O) feedback between the creators of fire weather tools and operational decision makers.

Steve Weygandt is the Chief of the Assimilation and Verification Innovation Division (AVID) 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. helped to direct the development of data assimilation systems that provide initial conditions for the Rapid Refresh (RAP) and High-Resolution Rapid Refresh (HRRR) models and has helped transition multiple versions of these models to NOAA operations since 2012. He is currently helping to direct the development of the Rapid Refresh Forecast System (RRFS) that will replace the RAP and the HRRR as the NOAA regional model application of the Unified Forecast System.

Scott Nahman

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.

Dave Turner is GSL's Senior Scientist. The focus of his research is to better understand various processes that act upon and within the boundary layer (e.g., convective initiation, turbulent redistribution of water vapor, aerosol, and energy, land-atmosphere interactions, etc.) and ultimately to improve the representation of these processes within numerical weather prediction and climate models. Part of this work includes continuing to develop and mature different ground-based profiling technologies to measure the temperature, humidity, and turbulent structure of the boundary layer, and using these observations to gain insight into how well NWP models (such as the high-resolution rapid refresh model (HRRR) which is developed in GSL) are representing atmospheric processes and evolution. Improvement in these processes will not only enable better forecasts of impactful (severe) weather, but also greatly benefit the renewable energy community.