NASA Programs at Duke University

Presented at NASA and North Carolina:

Building Stronger Partnerships

24 April 2002

Centennial Campus, North Carolina State University

NASA Strategic Enterprises

• Biological and Physical Research• Human Exploration and Development of Space• Aerospace Technology• Earth Science• Space Science• Educational Initiatives

Duke’s Strengths

• Medical Center and School of Medicine• Strong sciences departments• Small but outstanding Pratt School of Engineering• New Nicholas School of the Environment and Earth Sciences• Highly ranked private university

Breadth of Activity at Duke University

NASA currently funds research activities in eight departments in four schools.

• Pratt School of Engineering – Mechanical Engineering and Materials Science

– Civil and Environmental Engineering

– Electrical and Computer Engineering

• Nicholas School of the Environment and Earth Sciences– Earth and Ocean Sciences

– Duke Marine Lab

• The School of Medicine– Duke Center For Hyperbaric Medicine And Environmental Physiology

• Arts & Sciences– Physics

– Biology

Research Activities at Duke

• Prebreathe Reduction Protocol (PRP) Trials• Effects of Precipitation Variability and Desertification on Water Dynamics

in Arid Lands: A Patch and Landscape Modeling• Intense Lightning-Generated Electromagnetic Fields• Modeling of Unsteady Three-Dimensional Flows in Multistage Machines• The Mechanics of Flapping Flight• The Influence of Irrigation on Warm Season Precipitation in the Great

Plains• The Impacts of Land-Use/Land-Cover in Amazonia on

Hydrometeorological Processes at Different Spatial and Temporal Scales• An Investigation of the Geometrical Sealing Properties of Inflatable

Structures Used for Space Solar Power Generation

Can Increased Evapotranspiration Due to Irrigation in the Great Plains Alter Regional Climate?Stuart Rojstaczer, Duke University, PI

NASA Land Surface Hydrology Program

Goal and approach: Understand the feedbacks between landscape change and climate in an area that has been intensely irrigated over the last five decades. Compare precipitation patterns in summer months with patterns of intense irrigation. Use rain gage and radar data, as well as numerical models.

Figure 1. Texas Panhandle. Irrigated area outlined in black. Gauging stations in yellow and white.

Figure 2. Variability in precipitation (from radar data): c) 1st half summer 1997; f) 2nd half summer 1997; g) summers of 1996 and 1997 combined.

Results:

The cool, wet surface increases low-level instability, triggering storms. We estimate that an additional 6% to 18% of summer precipitation attributable to irrigation falls ~90 km downwind of the irrigated region.

NASA Prebreathe Reduction Protocol (PRP) Study

Principal Investigator: Richard D. Vann, Ph.D.Center for Hyperbaric Medicine and Environmental Physiology

Duke University Medical Center

Funded through NASA Cooperative Agreement NCC 9-83

• Scenario - Astronauts must decompress from normal International Space Station (ISS) pressure of 14.7 psia (1 atmosphere; equal to sea level) to work outside in space suits with an internal pressure of 4.3 psia (1/3 atmosphere).

• Problem - Pressure change is great enough to cause decompression sickness (DCS - pain, neurological dysfunction, possibly even death) from nitrogen (N2) bubbles.

• Standard Solution - Breathe oxygen (O2) prior to decompression (“prebreathe”) to washout

N2 from tissues and reduce DCS risk.

• Complication - Standard Space Shuttle O2 prebreathe is too long for the number of

spacewalks required to construct and maintain the ISS.

• Solution - We showed exercise during O2 prebreathe increased N2 washout and reduced

prebreathe time. We developed a procedure used on 12 ISS space walks since July 2001.

• Current Goal - Further optimize the exercise/prebreathe protocol for speed and safety.

Aeromechanics Research at Duke: The GUIde III Consortium

• High cycle fatigue of turbomachinery blading has large economic cost to airlines,engine companies, is a safety issue, and is a readiness problem for the military

• NASA, The U.S. Air Force, Engine Manufacturers have formed the GUIde Consortium to fund university researchers investigating HCF

• Industrial steering committee insures that work will produce data and methods that will be useful to engine companies and military

• Consortium is organized by investigator at Carnegie Mellon University, insuring research has appropriate intellectual content

Modeling Multistage Aerodynamics of Turbomachinery

• Understanding aerodynamics is key to predicting and controlling HCF in engines.

• Most aerodynamic models do not include multistage effects

“Physical Variability, Ecosystem Response and Biogeochemical Consequences in the Pacific Ocean: Understanding Oceanic Carbon

Cycling between 1950-2000” 

Modeling and Data Analysis in the EOS Interdisciplinary Science Program (EOS/IDS)

PI: Richard T. Barber (Nicholas School of the Environment and Earth Sciences, Duke University)

Co-Investigators: Fei Chai (U. Maine), Yi Chao (JPL-Cal Tech) and T-H Peng (AOML/NOAA)• 

•Predictive understanding of the ocean's role in carbon cycling requires the ability to specify how variability in temperature, winds or circulation affects the partitioning of carbon between the atmosphere, surface mixed layer and deep ocean.

•To better understand how physical variability affects carbon partitioning in the Pacific Ocean, especially on interannual and decadal time scales, we used a physical-biogeochemical model to produce a 50-year (1950-2000) retrospective analysis for the Pacific Ocean. The 10-component biogeochemical model simulates an oceanic food web including the major biological and chemical processes.

•The 50-year analysis shows the variability of phytoplankton blooms and atmospheric CO2 drawdown caused by physical variability at the temporal and

spatial scale of El Niño/La Niña events.

•Most excitingly, we have also resolved low-frequency changes in carbon partitioning associated with the Pacific Decadal Oscillation, a large-scale 18 – 30 year cycle of upper ocean dynamics.

  

 

Fig. 1: Typical wintertime Sea Surface Temperature (colors), Sea Level Pressure (contours) and surface windstress (arrows) anomaly patterns during warm and cool phases of PDO, the upper panel. The Pacific Decadal Oscillation (PDO) Index, the lower panel, is defined as the leading principal component of North Pacific monthly sea surface temperature variability (poleward of 20oN for the 1900-93 period).

The Pacific Decadal Oscillation (PDO) is a low-frequency pattern of Pacific climate variability. During the warm phase of the PDO, the pattern has cool SST anomalies in the central North Pacific and warm anomalies along the west coast of North America. The PDO tends to stay in phase (negative or positive) for decades at a time (18-30 yr period). When the PDO and El Niño-Southern Oscillation (ENSO) are both in the warm phase, as happened during the 1997-98 ENSO event, the anomalies in temperature and density can be extremely large in the equatorial Pacific. The PDO may have changed sign in the last year or so. How the sea-to-air CO2 flux will respond to these altered physical conditions in the equatorial

Pacific has important consequences for atmospheric carbon partitioning.

 

Fig.2: The normalized PDO index and modeled primary production (integrated from the surface to 120m) for the region of 5S-5N and 90W-180 between 1962 and 2000. During the negative PDO, before 1978, the equatorial Pacific was cooler and our model indicates that primary productivity was higher, resulting in reduced equatorial outgassing of CO2 to the atmosphere. Throughout the

1980s and 1990s, the PDO was in the positive phase and, therefore, productivity in general was lower.

Roni Avissar - Duke CEE

Project Title: A Study of Teleconnections Using a Nested Global Climate Model - Regional Climate Model and Satellite Observations

Project Description:Similar to the effects of El-Nino, Prof. Avissar finds that deforestation in the Amazon has a significant impact on the hydrometeorology of the planet. This study is conducted with a new generation of hydroclimate numerical model [the Ocean-Land-Atmosphere Model (OLAM) developed at Duke University by the PI and his team], capable of telescoping between regional and global scales using a series of nested, two-way interacting grids.

• Biological and Physical Research• Human Exploration and Development of Space• Aerospace Technology• Earth Science• Space Science

Duke will continue to be active in a number of strategic enterprises