Modeling the Water-Food-Energy Nexus in the Arab World : The Case of Egypt

THE NASA LAND INFORMATION SYSTEM

HAMADA S. BADR

APRIL 18, 2016

CONRAD - CAIRO, EGYPT

What is the Land Information System?• A system to study land surface processes and

land atmosphere interactions

• “Use best available observations” to force and constrain the models

• Support diverse datasets for meteorology, parameters, data assimilation, and evaluation

• Applications: Weather and climate model initialization, water resources management, natural hazards management

• LIS is open source and freely available: http://lis.gsfc.nasa.gov/

LIS is ScalableThe system is flexible to the resolution of available input data and to application needs

LIS Structure• Includes numerous advanced Land

Surface Models (LIS) to simulate water and energy balance

• LIS Data Assimilation (LIS-DA) modules support multiple assimilation algorithms and data types

• LIS optimization and uncertainty estimation (LIS – OPT/UE) allow for parameter calibration

• NASA Unified WRF (NU-WRF*) couples LIS to the WRF regional climate model

* Note: NU-WRF is not presently open source, but will be in a few months

The LIS Modeling Suite

• The Land Data Toolkit pre-processes all inputs

• LIS runs core simulation capabilities

• The Land surface Verification Toolkit provides output evaluation tools

• All are open source and use common data structures

LIS Outputs• A full suite of gridded hydrologic and energy

balance variables

• Routed river flow

• Includes customizable irrigation routines

• Some LIS LSMs actively simulate vegetation

LIS Policy Applications• LIS is the backbone of the Global Land Data Assimilation System (GLDAS). GLDAS is used in

numerous applications, including the World Resources Institute Aqueduct data portal.

• LIS supports the Famine Early Warning System Land Data Assimilation System (FEWS LDAS), which supports FEWS decisions on food aid distribution.

• LIS underlies the North American Land Data Assimilation System (NLDAS), which was used in the U.S. National Climate Assessment, is used by the U.S. Air Force Weather Agency for weather forecast initialization, and is an input to the U.S. Drought Monitor (USDM), which determines U.S. Federal crop insurance pay-outs.

• LIS is being used for research level drought monitoring and water resource analysis in South Asia, South America, the Middle East, and Australia.

LIS Strengths• Flexibility: multiple LSMs, data readers, DA capabilities, etc.

• Sophistication: includes cutting edge models with advanced physics and satellite-informed parameterizations

• Power: supports multi-model ensemble simulations across scales

• Customization: entirely open source, with a systematic structure to allow for custom development

• Community: LIS is used by several leading research groups in the U.S. Now that it is open source (a recent development) this community of practice is expected to grow rapidly

LIS Weaknesses• Computing requirements: LIS runs best on Linux servers with significant computational power.

• Learning curve: The system takes practice. Even learning how to plot output can take time for a user who is not familiar with scripting tools.

• Surface and Groundwater Interactions: LIS includes simple lake models, river routing, and some representation of unconfined groundwater. But it is not a groundwater model, and it cannot represent complex surface water interactions (e.g., salt water intrusion). The LSMs are 1-D.

• Calibration: Fully distributed LSMs are extremely difficult to calibrate. LIS has tools to help, but it’s not the right approach if the goal is to fit data rather than understand process.

In sum: LIS is powerful, but it is a commitment.

Thank You