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Unformatted text preview: 9/27/2007 Course format
Lectures on Tuesday & Thursday Try to do reading before lecture Choice of 3 section meetings (Tue, Wed or Th) Discussion of lectures and readings P bl Problems and questions d i T.A. Carl Legleiter, PhD student Grading Homework 25% (groups) Midterm 25% Final 50% Thresholds A/A- 85% B 70% C 50% Regrading policy
2 Availability of Help
Ask questions in class. A favor to classmates. Participate in lab discussions. Practice professional p problem-solving roles. g Office hours Tom & Jeff are generally available when and where you find us.You can also make an appointment via email. Carl will post his office hours to the class email list. firstname.lastname@example.org email@example.com tdunne@bren ucsb edu firstname.lastname@example.org email@example.com (faculty, T.A., and students) 4 Honor Policy
We encourage you to collaborate in learning and problemsolving, including on homework problems. Although you do the homework in groups, make sure that you each understand what your group did. Make calculations yourself. y g p y Everyone contributes to the write up of the answers. Objective of the Course
The course is dedicated to the proposition that there is value to the environmental manager and the citizen in understanding that you live on a planet. So, it functions like a planet! Its planetary functions will affect the way you live and the way you will do business throughout your professional career. You can b blind-sided by this fact, or be be b s t s act, o b on top of it. In this course, we want you to practice thinking about managing environmental problems using this insight.
3 5 The midterm and final examinations will be take-home.You must not discuss them or collaborate with anyone in locating sources or articulating answers to these questions. We expect you to use the Web, even for take-home exams. But you must report the source and nature of your y p y internet use, so that we can check your interpretations. Your willingness and ability to conduct yourself in this way is an important part of your professional education, and we treat it very seriously. ESM 203 1 9/27/2007 How Earth operates (simplified)
less The system components interact
Distribution of solar radiation affects the energy balance of Earth (through clouds, snow/ice cover, and regional transfers of latent heat). Regional balances of precipitation, evaporation, and continental runoff affect the salinity, temperature, and density of ocean water. 1370 Wm2 Ocean circulation is driven by wind, but these density differences drive vertical circulation. Distribution of continents and ocean basins affects ocean circulation
Some fraction (20-30%) is reflected by atmosphere and surface Remainder (70-80%) is absorbed and emitted at longer wavelengths Some emitted radiation is absorbed in atmosphere Imbalance between Equator and Poles causes circulation of atmosphere and ocean Heated surface transfers energy to atmosphere Water at surface evaporates and moves into atmosphere and the energy ... and condenses to fall back to surface as precipitation also moves Precipitation is a first-order influence on terrestrial productivity, natural and cultivated. Water is the primary agent mobilizing lithospheric materials and transporting them as soils, sediments, and solutes, which influence the construction, nutrition, and pollution of ecosystems. } 6 Earth System Science
Earth consists of system components "Solid" planet Ocean Atmosphere Hydrosphere Cryosphere Continental "near surface" (pedosphere and biosphere) "Technosphere" p Interactions
The components interact in ways and at rates that affect humans (habitability, productivity, hazards) Atmosphere + lithosphere landslide hazard Ocean + atmosphere El Nio flood/drought Atmosphere + technosphere global warming The interactions change through time at rates that affect humans Thus, it is difficult to establish a baseline condition against which to recognize trends It is difficult to build consensus about which changes are "significant", "negative", etc. 7 9 ESM 203 2 9/27/2007 Interactions (cont.)
Humans (technosphere) are so widespread, numerous, and intensive users of resources that we now affect the nature and rates of these interactions. Our presence is now big enough to affect the planet. This emerging (post-1970) realization confronts us with two sets of issues How do these global-scale processes affect us? Can we do anything to adjust to the consequences and/or mitigate our impact? Scales
Consequences of planetary behavior and opportunities for managing/adjusting to them exist at a range of temporal and spatial scales. Natural and social resources at these various scales lie within the responsibilities, knowledge, and interests of different specialists within our societies. These features again make consensus about existence, significance, and timeliness hard to develop. This is where Bren graduates come in. But we don't know what our needs or options are until we p understand the nature of the systems that we are impacting and adjusting to. Hence, "Earth System Science for Environmental Management"
10 12 Earth System: physical climate and biogeochemical systems, coupled by hydrologic cycle Global scale issues
The course emphasizes the value to the environmental manager of understanding global-scale processes global climate change radiation balance of Earth origin of persistent weather patterns global tectonics as the setting for landscape types and functioning spatial and temporal variations in ocean circulation ESM 203 3 9/27/2007 Local scale issues
Some of the course material is relevant to the analysis of local issues, e.g. soil and groundwater recharge energy and water balance of a land surface water supplies Need for Predictions
Technological societies increasingly demand predictions -- or at least explanations -- of these complex interactions: Will climate change diminish the Sierra Nevada snowpack and require i i investments i water storage f iliti or change water use? t t in t t facilities h t ? Will the Arctic Ocean ice duration and thickness diminish and open oil/gas exploration and navigation between Siberia and East Asia in the next 50 yr? At what rate will soil erosion reduce the water-holding capacity and fertility of soil profiles? Should we do anything about it? What causes the catastrophic burning of the rain forest, resulting in air pollution and air traffic problems throughout South and Southeast Asia and widespread inundation of agricultural land in Southeast Asia during severe El Nio years? Is the international insurance industry adequately funded if its exposure to environmental risks is increasing? You can address problems of this nature using the physical principles we teach even if "addressing" means only participating in the debate about what are critical issues and which specialized analysts p y need to be recruited Local scale issues (cont.)
Later, elective courses (e.g. Groundwater Hydrology, Watershed Analysis, Mountain Snowpack, Fate and Transport ...) facilitate more local analyses. But you should be able to examine issues that appear at first to be only local or regional within the context of the fact that the "globe" changes. You will also notice that we teach a `process-oriented' approach to the definition of problems and to the search for solutions at all scales. Recent example
Source: Environmental Finance 27 August 2006 More insurance solutions needed on climate US insurance companies have made an encouraging start in developing policies to combat climate change, but more effort is needed, according to a US-based investor group. "We've seen encouraging progress from big-name insurers and brokers We ve big name since last year's devastating hurricanes, but many more creative services will be needed as we confront what is perhaps the biggest threat in the industry's history," said Mindy Lubber, president of Ceres, a coalition representing more than 50 institutional investors with a total of $3 trillion under management ESM 203 4 9/27/2007 Need for predictions
Economist, Kenneth Boulding (1973)
"...whereas all experiences are of the past, all decisions are about the future... it is the great task of human knowledge to bridge this gap and find those patterns in the past which can be projected into the future as realistic images ..." Environmental models are hard to verify or refute
(unlike models of controlled systems in lab experiments) Therefore useful environmental models are based on a clear conceptual model expressing best current understanding; facilitate communication; express uncertainties; encourage active building of consensus decisions, instead of promoting passive or self-righteous decisions. The sharing of conceptual models between contending groups is a first step towards conflict resolution and to agreement about which other types of models will be credible to all groups.
18 Prediction (cont.)
Science has become valued, to various degrees, as a provider of predictions and explanations. Explanations and predictions by scientists are only one component of efforts that humans make to understand what is happening to them, and to adjust to what they sense. ["That's just the scientists' point of view!"] Qualitative and quantitative predictions are most useful when based on an understanding of mechanism. Use of science for understanding
Science didn't evolve for the purpose of environmental dispute resolution. Scientific understanding of environmental processes emerges gradually, and sometimes untidily, because the processes are complex, involve positive and negative feedbacks, and evidence of their behavior is obscured by the signatures of other processes. Results of scientific investigations (as with other human endeavors) can be distorted and manipulated. 19 ESM 203 5 9/27/2007 Modern CO2 concentration in Earth's atmosphere, ppm (http://cdiac.esd.ornl.gov/) http://cdiac.esd.ornl.gov/)
380 Temperature trends corresponding to CO2 increase (Karl & Trenberth 2003) (Karl 2003) 370 360 Mauna Loa South Pole Siple CO2, ppm 350 340 330 320 310 1950 1960 1970 1980 1990 2000 22 400+ thousand years of CO2
Mauna Loa South Pole Siple Vostok Questions a skeptic might ask
How do we know that the recent increase in CO2 is caused by human activity?
350 The ocean has a much larger reservoir of carbon than the atmosphere. t h
Could the cause of the recent increase in CO2 be related to ocean warming, caused by some other (natural) mechanism? That is, is the increase in CO2 a result rather than a cause?
CO2, ppm 300 250 Why do we think that increasing CO2 is causing the rise in temperature, rather than some other mechanism? Big temperature changes, often rapid ones, have occurred before there were many people. h l Solar radiation varies. Ocean circulation has long-term cyclical variability. Big volcanic eruptions lead to atmospheric aerosols that block sunlight and cause cooling.
23 200 150 450 400 350 300 250 yr BP 200 150 100 50 0
Thousands ESM 203 6 9/27/2007 Is the extra CO2 from fossil fuels?
The ice core data show the rise in CO2 to start with the Industrial Revolution. The average South Pole CO2 concentration lags a year or two behind Mauna Loa, indicating that the "extra" source is in the Northern Hemisphere. Can we account for the temperature increase without the CO2?
No. We will cover some of this research in the course. Lean 2005 addresses the variability of the Sun Sun. Crowley 2000 explains much of climate variability through the last millennium but cannot get the most recent warming through other mechanisms. moderately unstable isotope of 12C, is produced continually by decay of 14N from cosmic rays in the upper atmosphere. Half-life of 14C is 5730 yr, so fossil fuels have essentially none. Since 1890, the 14C/12C ratio in wood has declined by about 2%.
CO2 persists in the ocean for centuries, not millennia, so ocean 14C would not account for this difference. Calibration of this "Suess effect" is necessary for radiocarbon dating. 14C, a We have to answer this question with models, because we have no historical analogue. g Our confidence in models depends on their ability to reproduce temporal and spatial variability. Rise of CO2 with the Industrial Revolution
375 Credibility of scientific understanding
The credibility of a scientific idea rises or falls according to its ability to meet repeated challenges proposed by skeptics, including other scientists, people and institutions to which particular scientific information is unwelcome, including scientific advisors aligned with such interests. 350 Mauna Loa South Pole Siple CO2, ppm 325 Skepticism is good. "An expert understands the source and magnitude of error in his or her own work." David Simonett, founder of UCSB's Geography Dept.
1750 1800 1850 1900 1950 2000 300 275 1700 27 ESM 203 7 ...
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This note was uploaded on 08/06/2008 for the course ESM 203 taught by Professor Dozier,dunne during the Fall '07 term at UCSB.
- Fall '07