Introduction to Earth System ScienceArizona STEM Workshop
Systems Synergy: Interrelation of the Spheres
1. Some big picture Earth System Science (ESS) questionsa. our planet 700 Myr agob. our planet 50 Myr agoc. why is Earth so different?d. our planet today
2. What is ESS and why is it different?a. interaction of the spheresb. systems dynamicsc. modern society, understanding, and decision-making
3. Systems examplesa. radiative balanceb. long-term C-cycle
4. Big questionsa. The PETMb. Snowball Earthc. modern climate change
5. Concluding thoughts
Dan Schrag & Paul Hoffman; http://www.snowballearth.org/
Our planet 650 million years ago?
NASA/JPL
The north pole of our planet today
H. Brinkhaus, 2006
H. Brinkhaus, 2006
Paleogeography 50 million years ago
Geodetic Hills, Axel Heiberg island
‘Napartulik’ - Inuk for ‘Place of Trees’
Courtesy Jane Francis
H. Brinkhaus, 2006
Fossil Forest Ridge, Geodetic Hills
Buchanan Lake FormationMid Eocene fluvial sediments
(image courtesy Jane Francis)
H. Brinkhaus, 2006
• Fossil leaf litter layers represent forest floors
Courtesy Jane FrancisH. Brinkhaus, 2006
All fossil material is mummified - dried and slightly compressed
Courtesy Jane Francis
H. Brinkhaus, 2006
Some leaf litter layers are dominated by Dawn Redwood leaves (Metasequoia). These represent lowland swamp forests.
Courtesy Jane Francis
H. Brinkhaus, 2006
Metasequoia has light feathery leaves, triangular shape and an open structure, which would have been ideal for growing at high latitudes with low angle light
Metasequoia is a deciduous conifer. It was discovered first as a fossil, then found living in China
Courtesy Jane Francis
Brinkhaus, 2006
There are many fossil forests preserved within mid Eocene strata (~50 Ma) in the Canadian High Arctic
The forests lived at 80°N, within 1000 km of the North Pole,
…nearby there were also crocodiles…
Huber, 2009
Our planet 50 million years ago?
mean annual temperature (°C)
modern mean annual T: -10 to 0 °C)
modern mean annual T: 20-25 °C)
Why is Earth so different (fortunately for us) from nearby planets?
No plate tectonicsSurface T ~ 480 °CClouds of sulfuric acidAtmosphere: 92 bars;96% CO2; 3% N2
Active plate tectonicsSurface T ~ 15 °CClouds of waterAtmosphere: 1 bar;77% N2; 21% O2; 0.038% CO2
Source: http://cires.colorado.edu/science/groups/steffen/greenland/melt2005/
Welcome to the Anthropocene
Does this emitted CO2 really have an impact on CO2 concentration of the whole atmosphere?
Source: http://cires.colorado.edu/science/groups/steffen/greenland/melt2005/
Welcome to the Anthropocene
Source: http://cires.colorado.edu/science/groups/steffen/greenland/melt2005/
Welcome to the Anthropocene
1. Some big picture Earth System Science (ESS) questionsa. our planet 700 Myr agob. our planet 50 Myr agoc. why is Earth so different?d. our planet today
2. What is ESS and why is it different?a. interaction of the spheresb. systems dynamicsc. modern society, understanding, and decision-making
3. Systems examplesa. radiative balanceb. long-term C-cycle
4. Big questionsa. The PETMb. Snowball Earthc. modern climate change
5. Concluding thoughts
What is Earth System Science, anyway?
Disciplinary Science
Inte
grat
ion
ESS
Dec
isio
n Making
Interpretation
ES
S
Johnson et al., 2000
There are many other ways to view ESS...
http://www.cotf.edu/ete/ESS/ESSmain.html
http://serc.carleton.edu/introgeo/earthsystem/nutshell/
Earth system science is a way of understanding the Earth as a synergistic system of interrelated phenomena and reservoirs that interact through transfer of matter and energy.(paraphrased from http://esse21.usra.edu/ESSE21/)
Many ESS approaches emphasize interactions among the “spheres”
lithosphere-hydrosphere-atmosphere-biosphere± cryosphere, pedosphere, asthenosphere, etc.
Many ESS approaches also emphasize
system dynamics, feedback loops, and cycles
Economic and job growth in Environmental-related fields:
A Clean Energy FutureAnother set of occupations with strong growth potential are in fields related to clean energy production and environmental protection. There are growing opportunities in these fields, particularly for workers with technical skills.For example, Figure 4 shows the past and future growth of environment-related occupations compared with all other occupations between 2000 and 2016. The environment-related jobs we consider are environmental engineering technicians (see box), environmental engineers, environmental scientists and specialists (including health), and environmental science and protection technicians (including health). Clearly, the U.S. labor market is already becoming increasingly "green" through the growth in these occupations. Jobs devoted to environmental improvement grew far faster than other occupations from 2000-2006 and the BLS projects fast relative growth through 2016. These environmental jobs account for only a small fraction of a growing list of occupations and industries that are becoming increasingly devoted to clean energy production, energy efficiency, and environmental protection.
http://www.whitehouse.gov/administration/eop/cea/Jobs-of-the-Future/
“Schendler has also learned firsthand a point that climate scientists have been making for some time: With climate change, "warming" isn't the only—or even the most serious—challenge. The sheer interdependence of complex ecosystems systems can grease you. “
Examples of industry/political interest in climate change:
•alternative energy•CO2 capture & sequestration•shifts in agriculture•rising sea level•C-footprint calculations•new shipping routes•water supply•insurance of natural disasters•impacts on ski areas, tourism, rec•long-term “weather“ prediction•human migration
“... politicians, as a species, may need to adapt to climate change as fast as polar bears. Consider the ways the electoral environment could be affected: Both major political parties could see their power bases erode as Americans, responding to warming temperatures and rising seas, flee the Republican-dominated South and Democratic-friendly coasts. Drought in the Southwest could reignite water wars between California suburbanites and Rocky Mountain swing voters. In Iowa, where floodwaters will rise more often and corn yields could suffer from heat waves and insect plagues, wanna-be presidential contenders could end up talking FEMA as much as the farm bill.
And if you think the current immigration debate is charged, wait until so-called climate refugees begin pouring in from China, Southeast Asia, and Sub-Saharan Africa. Meanwhile, on the foreign-policy front, the NOAA study projects "tensions between governments in the East and West [will] begin to fray as it is becoming clear that an entirely new level of commitment"—read: huge amounts of money—"will probably be needed to address the relationship between people and the planet."
Raupach et al. 2007, PNAS
Recent emissions
1990 1995 2000 2005 2010
CO
2 E
mis
sion
s (G
tC y
-1)
5
6
7
8
9
10Actual emissions: CDIACActual emissions: EIA450ppm stabilisation650ppm stabilisationA1FI A1B A1T A2 B1 B2
1850 1900 1950 2000 2050 2100C
O2 E
mis
sion
s (G
tC y
-1)
0
5
10
15
20
25
30Actual emissions: CDIAC450ppm stabilisation650ppm stabilisationA1FI A1B A1T A2 B1 B2
20062005
Current emissions are tracking well above the most intense fossil fuel scenario envisioned, A1FI- A1 Fossil Fuel intensive; and moving away from stabilization scenarios of 450 ppm and 650 ppm.
2007
Nature, 22 April 2010
1. Some big picture Earth System Science (ESS) questionsa. our planet 700 Myr agob. our planet 50 Myr agoc. why is Earth so different?d. our planet today
2. What is ESS and why is it different?a. interaction of the spheresb. systems dynamicsc. modern society, understanding, and decision-making
3. Systems examplesa. radiative balanceb. long-term C-cycle
4. Big questionsa. The PETMb. Snowball Earthc. modern climate change
5. Concluding thoughts
What controls surface T of Earth?
energy flow from sun to Earth: 173,410 W
geothermal energy flow from Earth: 44 W
Albedo:
fraction of sunlight (radiant energy) reflected back into space
Atmospheric greenhouse gases:
above: dry air composition
H2O
CO2
CH4
O3
CFC-11 CFC-12
N2O
incoming
outgoing
greenhouse effect• With no greenhouse effect T = -21 °C• With greenhouse effect T = +15 °C• GHGs on Earth are the difference between ice and
liquid water: no-life and life
Some illustrative feedbacks involving:
incoming solar radiationalbedo
GHGs
rock cycle
Ts
System dynamics:
Positive feedback loop (destabilizing)
Implications of the ice-albedo feedback
1. runaway warming and loss of all ice?
2. runaway cooling and global ice cover?
chemical weathering of silicate minerals removes CO2 from the atmosphere
silicate weathering
higher T → higher precipitation and faster weathering rates
System dynamics:
Negative feedback loop (stabilizing)
silicate weathering
Implications of the long-term carbon cycle
over the last ~500 Myr the global carbon cycle has moderated Earth’s surface temperature to within ~20-30 °C
1. Some big picture Earth System Science (ESS) questionsa. our planet 700 Myr agob. our planet 50 Myr agoc. why is Earth so different?d. our planet today
2. What is ESS and why is it different?a. interaction of the spheresb. systems dynamicsc. modern society, understanding, and decision-making
3. Systems examplesa. radiative balanceb. long-term C-cycle
4. Big questionsa. The PETMb. Snowball Earthc. modern climate change
5. Concluding thoughts
Lone Butte, North Dakota
Photo: Brett Tipple
Zachos et al., 2001
the PETM as recorded in ocean sediments
Zachos et al., 2001
The PETM•5-8 °C global warming over 10-40 kyr
•~5000 Pg of C released (this year humans release ~9 Pg C)
•major ocean acidification, dissolution of several km of limestone
•foraminiferal extinctions•major biotic shifts, climate changes
•widespread wildfires
Where did the C come from?
http://www.snowballearth.org/
http://www.snowballearth.org/
http://www.snowballearth.org/
http://www.snowballearth.org/
http://www.snowballearth.org/
http://www.snowballearth.org/
http://www.snowballearth.org/
http://www.snowballearth.org/
1. Some big picture Earth System Science (ESS) questionsa. our planet 700 Myr agob. our planet 50 Myr agoc. why is Earth so different?d. our planet today
2. What is ESS and why is it different?a. interaction of the spheresb. systems dynamicsc. modern society, understanding, and decision-making
3. Systems examplesa. radiative balanceb. long-term C-cycle
4. Big questionsa. The PETMb. Snowball Earthc. modern climate change
5. Concluding thoughts
Earth System Science
1. ESS is different in that it:a. regards connections between spheresb. examines states and changes vis a vis system
dynamicsc. tends to focus on effects with clear impacts on
habitability2. ESS provides a foundation for integration and
interpretation involving energy, resources, climate, land-use, biodiversity, economics, policy
3. ESS is science, not a call to personal “green virtue”...but...4. ...the stakes are high nonetheless...