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^ Program
Futures of Life
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• Data Mining and Data Fusion for Earth Science
• Earth Systems and Models for Astrobiology
• Collaboration: Disciplines & Institutions
• Earth Science & Astrobiology
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Co-Leads: Hector D’Antoni and Lynn Rothschild with Jay Skiles
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The Futures of Life module will include collaboration with the DEVELOP Educational Program directed by Jay Skiles.
Purpose
"Our Earth as a system" is our paradigm to search for life elsewhere in the Universe. Earth Science focuses on Goal 6 of the Astrobiology Roadmap - how a living planet gains a living system and what conditions will eventually cause that living system to expire. In 2004 we will hold a round table to explore design of a future module to address this theme.
1. Yellowstone National Park: terrestrial analog studies, such as this search for extremophiles. 2. “Ox-eye”: the famous landmark for astronauts in the Mauritanian desert caused by sediment from primeval ocean being pushed up to the Earth’s surface. 3. Blanca: tropical storm. 4. A mission to a deep ocean vent.
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Background
The future of Earth is a key question of Astrobiology that has received insufficient attention. Life operates in a physical environment, which is changing because of global changes (CO2, UV flux) to planetary factors, such as our relationship to the moon and the age of the sun. In an effort to develop collaboration between other NASA-funded Earth Science education programs and NASA University (NASA U), we are working with the DEVELOP Program, which started in 1998 at Langley Research Center and expanded to include ARC in 2003. Cross-over between NASA U and DEVELOP enables NASA U students to address astrobiology questions that deal with the continuation of life on this planet, changing ecosystems on Earth, and the ease or difficulty with which ecosystems can be modified and controlled by humans.
Astrobiology questions about the Futures of Life on Earth are addressed by studies of Earth Systems and Models, which interpret past and present data, enabling us to find patterns and identify trends, a prerequisite to make meaningful predictions about the future.
Astrobiology's focus on the origins of life and the formation of planetary systems is complemented by understanding the life cycle of the Earth (and other planets suspected of once harboring life) in the context of cosmic changes.
Life on Earth has modified the environmental conditions required to sustain itself and its evolution for billions of years. Knowledge of these changing Earth conditions serves as a model for understanding how a planet can maintain a living system. Earth, as the only living planet known to humans, is the only model that can inform our efforts to search for evidence of life beyond Earth.
The NASA Earth Science Enterprise is studying Earth on a truly planetary scale: its geography and geology, climate, lithosphere, oceans and water systems and biosphere. Humanity excels, as no other species ever has, in altering all other systems upon which its survival depends, e.g. global warming caused by the greenhouse effect.
The Earth Science Enterprise aims to understand our Earth as a system in order to predict its future. NASA brings to this study the unique perspective of space. The technologies, models and data that NASA assembles can guide astrobiologists in the design of a spectroscopic search for life elsewhere through the use of a wide array of remote sensing devices. Our Earth also provides the criteria for a sustainable biosphere - the "terrestrial paradigm."
Carefully calibrated observations are assimilated into data systems, providing the long term data record used to model each part of the Earth system. Astrobiology contributes to this Enterprise by taking a longer look into the past, testing and calibrating models of processes that change slowly, such as glaciation. Thorough measurement of Earth helps us to perfect observational techniques for space science. Models built to explain Earth systems today can also be used to model ancient living systems on Earth and processes on other planets.
For example, we build an analog of the biosphere of a planet that is cooling and drying (i.e., leaving the habitable zone around its star). We selected South America to build the analog because of the continent's large N-S gradients in temperature, precipitation, and biodiversity. In order to explore the analog, we contrasted two time scales. On the one hand is the long-term scale that produced today's biogeography (~10Ka); on the other are intense, global disturbances, such as the "El Niņo" Southern Oscillation (ENSO), which occur within one year. We have identified the best spatial resolution to show the effects of these short-term disturbances and linked them to some of the stronger ENSO drivers, such as the sea surface temperature (SST). We have reconstructed the SST at 1-year resolution from 1246 through 1995 and are now extending our reconstruction back to the year 300 B.C.
Current work links satellite data of vegetation with ground level measurements of vegetation parameters such as chlorophyll concentration, photosynthesis rate, respiration, leaf area and others. This data feeds ecosystem-process models, which predict fundamental ecosystem parameters, such as net primary productivity. Once the model is parameterized with modern data, we are able to hindcast (as opposed to forecast) past environments using paleoclimate and paleoecology proxy data, such as pollen grains or tree rings. We can then cross validate our reconstruction with reconstructions based on other proxy data collections (e.g. foraminifera). This research links space science and technology to quantitative paleoclimatology and paleoecology. It develops the reconstructions to increase the time window on which current forecasting models operate.
In addition, knowledge of the ecological systems needed to sustain humans on Earth is a prerequisite to design life support systems for astronauts. So Earth's ecosystems serve as models for how to sustain humans for long duration missions to other parts of our solar system.
Research Plan
We will hold one or more Round Tables to explore design of a new module for FY 05. A 2004 Round Table will explore possible DEVELOP summer projects that overlap with the questions of NASA U. Focus will be on DEVELOP projects that address the Astrobiology Roadmap, specifically in the areas of origins of life, and the evolution of life and its ecosystems on this, and possibly other, planets.
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