Earth System Science
Geog788W Group 1
Fall 2004
Lars Bromley
Justin Goldstein
Andrew Johnston
Jyoteshwar Nagol
Haihong Yang
Alina Yohannan
“It is hard to imagine a more important discipline than Earth System
Science” – John Lawton in Science magazine, June 15, 2001
Earth Systems Science is the study of:
Interactions between oceans, atmosphere, living things, geologic
processes, land surface dynamics, and human systems.
Processes that connect biological, physical, and human systems operating
near the Earth's surface.
How interrelationships between physical and biological systems impact
each other and lead to changes.
Earth Systems Science
A prime focus of Earth System Science is the study of past and future changes in
Earth systems: Paleoclimate, Global warming. Strategies have been developed
to address climate change. (Group 3)
Special attention is paid to how human activities lead to changes in linkages
between systems and the response from humans to those changes: “Global
Change” research. (Group 1)
Range of topics dealing with the carbon cycle, water cycle, food production,
biodiversity, land-use change and its feedbacks on climate change and
variability.
ESS studies many different systems, each defined by its own sets of characteristics
and subsystems. Physical systems: atmospheric chemistry, cryosphere,
hydrosphere, energy transfer. Biological systems: marine life, terrestrial
ecosystems, biogeochemistry. Humans: land use, atmospheric changes.
External forces: volcanism, sun, solar system (orbital mechanics, impacts).
Geospheres
Atmosphere
Anthroposphere
Biosphere
Hydrosphere
Lithosphere and Pedosphere
How is Earth System Science performed?
System Science grew from work in biology and other fields in the mid1900s, applied to Earth Science in the 1990s. (Group 1)
In ESS simplified models are created to describe connections between
biological, physical, and human systems. Bretherton diagram.(Group 1)
The Earth system is a network of self-organizing systems connected by flows
of gasses, energy, nutrients. The global system: Gaia. (Group 2)
Most ESS research projects are focused on small parts of the Earth system.
Remote Sensing is a key part of ESS: NASA’s Earth Science program.
How is ESS different from other types of science?
ESS deals with the relationships between physical and biological systems
instead of the systems themselves.
Earth System Science uses holistic rather than reductionist approaches.
Earth System Science is interdisciplinary, including many academic
disciplines No single discipline can fully address the scope of ESS.
Geography and Earth System Science
Earth System Science is
inherently spatial. It
uses many scales
space (from the
particle to global)
and in time.
The interdisciplinary
nature of the science
and its focus on
connections between
systems makes it
attractive to
geographers.
Mitchell K. Hobish, Earth Systems Science, Section 16, Remote Sensing Tutorial
http://rst.gsfc.nasa.gov/Sect16/Sect16_3.html
Development of ESS – 19th Century
•
John Lawton wrote in Science (2001): ESS is still a young and growing field
(Science, 292: Issue 5524, v1965, June 15, 2001).
•
1802: John Playfair expounds on the life work of James Hutton – The
Principle of Uniformitarianism and the radical idea that “present is the key to
the past.”
•
1832: Lyall also builds on Hutton to describe earth processes
•
Agassiz et al. 1840 – glaciers responsible for forming large scale landscapes
•
William Morris Davis describes the “Geographical Cycle” and contributes to
geomorphology
Source: All bullets except the first taken from: http://geog.queensu.ca/gilbert/Supplementary Reading Lecture 201.pdf
Development of ESS – 20th Century
With an emergence of systems science (or systems theory) scientists
focused more on interactions between components of systems rather than
single-discipline studies.
Advances in nuclear physics led scientists to more effectively measure the
age of the Earth (http://geog.queensu.ca/gilbert/Supplementary Reading
Lecture 201.pdf)
1980s: scientists understand that humans are altering the physical sphere
and thus try to understand global change as involving integrated human
and physical systems. Beginning of the use of the term “Earth System
Science.” (http://www.usra.edu/iai/scotland.html)
1986: Francis P. Bretherton (U. of Wisconsin) developed the “Bretherton
Diagram” as chair of a committee which authored a seminal work in the
modern ESS field: "Earth System Science: A Closer View."
The Bretherton Diagram- Complex
Mitchell K. Hobish, Earth Systems Science, Section 16, Remote Sensing Tutorial
http://rst.gsfc.nasa.gov/Sect16/Sect16_3.html
The Bretherton Diagram- Simplified
The Bretherton Diagram- Explained
•The diagram depicts the
Earth System and is
comprised of sub-systems
(in turn comprised of subsystems, etc.)
•Given its roots in system
science, the sub-systems
and their interconnections,
couplings, and dynamics
are equally emphasized when one system acts
another reacts, etc.
The Bretherton Diagram- Main Components
1) The Physical Climate
System
2) Biogeochemical Cycles
•Within these broad areas
are sub-systems:
atmosphere, hydrosphere,
lithosphere, and the human
dimension.
•Because output from one
system is the input into
another, none of these
categories can be evaluated
in isolation.
Source: What is Earth System Science? Donald R. Johnson, Martin Ruzek, Michael Kalb. Proceedings of the 1997 International Geoscience
and Remote Sensing Symposium. Singapore, August 4 - 8, 1997.
Sub-System Example: Ocean Circulation
Source: Ocean Modeling. Center for Climate System Research, University of Tokyo.
Bretherton Diagram: Temporal Scales
Processes throughout the Earth system operate at different temporal scales:
• millions/billions of years: evolution of solid earth structures, atmosphere, etc.
• hundreds of thousands to millions: climate oscillations, species distribution, soil
development, etc.
• decades to centuries: physical climate system (weather patterns), some
biochemical processes like carbon, nitrogen, etc.
• days/seasons: Earth responds to weather, plant growth, decay
• day: heating and cooling, catastrophic events (volcanoes, earthquakes)
Source: Global Change and Our Common Future: Papers from a Forum Commission on Physical Sciences,
Mathematics, and Applications. National Academies Press. 1989.
Human Dimension of Global Environmental Change
Global Change is concerned with the nature and consequences of anthropogenic
perturbations in the interacting physical, chemical and biological and social systems
that regulate the environment supporting human life and influence the quality of that
life on planet Earth.
Global change research initially focused almost solely on the physical and biological
sciences, but in the last eight to ten years, there has been more recognition of the human
dimensions and the essential role that social science must play in resolving global
environmental problems.
Three problems that have been given greatest attention -- climate change, ozone
depletion, and loss of biodiversity -- are all anthropogenic in origin.
Planning for social science research on the human dimensions of global environmental
change began in 1986, significantly later than the planning for global change research in
the natural sciences.
Human Dimension of Global Environmental Change
Human interactions are included in the Bretherton diagram, but only as a “black
box”.
Understanding of large scale environmental change requires an integrated view
of how those spheres and humans interact mutually within the Earth System. Also
needs the cooperation between natural and social scientists.
The research of human interactions on global change and sustainability needs
the equivalent of a Bretherton diagram to visually convey the interconnections
among diverse cultural, economic, political, social, and institutional phenomena
and to begin to relate these theoretically.
Social Process Diagram
http://cesimo.ing.ula.ve/GAIA/SPD/spd_image.html