1、GEO 130 Earths Physical Environments,Introduction to Physical Geography,Define physical geography Explain how we study physical geography List several types of models Describe and define models List the factors that complicate the study of pattern and process and provide examples Give examples of ho
2、w scale influence the perception of pattern and process Explain how contingent historic events complicate the interpretation of pattern and process Explain the difference between non-linear and linear change Explain why models are limited in describing patterns in the environment Define and give exa
3、mples of positive and negative feedback Define/explain: steady state, dynamic equilibrium, phase shifts, and transient states,What is Physical Geography?,Integrated study of three subdisciplines Climatology Biogeography Geomorphology,What is Physical Geography?,Includes the role of humans and their
4、influence on natural processes,Why study physical geography?,The natural world is as complex as the human world Consider these facets of the Earths surface Its extent (size) and resolution (detail) History and time since origin (4.5 billion years),Why study physical geography?,To understand human-en
5、vironment interaction, you need to understand how the non-human world works.,How do we do physical geography?,We document pattern and process,We use models to study pattern and process,Models are a simplified, often idealized representation of reality. Intent of a model is to recreate patterns by ca
6、pturing the underlying explanatory processes Your role is to learn models, recognize they are idealized, and try to identify why they are incomplete.,What are the types of models?,Graphical conceptual models,Types of models,Maps,Types of models,Data visualizations and simulations Mathematical in ess
7、ence, but enhanced through computational power of the computer.,Types of models,Dynamical models Use field-derived conditions to model the behavior of a phenomena Can be used to predict or forecast the future,http:/moe.met.fsu.edu/tcgengifs/,Types of models,Dynamical models can also be used to hindc
8、ast the past and study events that have already happened,Types of models,Statistical models Use the record of the past to predict the future,What complicates the study of pattern-process?,1. Multiple driving variables,Driving variables are most directly responsible for the observed patterns. They ha
9、ve to be identified, but are not always readily apparent or easily separated from each other,Proximate and ultimate causation,A proximate cause is an event which is closest, or immediately responsible, for causing some observed result. This exists in contrast to a higher-level ultimate cause which i
10、s usually thought of as the “real“ reason something occurred.,Why did the ship hit the rock?,Proximate cause: Because the ship failed to change course to avoid it. Ultimate cause: Because the ship was under autopilot and the autopilot received bad data from the GPS. Separating proximate from ultimat
11、e causations frequently leads to better understandings of multiple driving variables,2. Contingent events,What contingencies complicate the prediction of wildfires?,3. Feedbacks,Feedbacks make prediction of the outcome of interactions difficult Positive feedback: externally generated change is reinf
12、orced Negative feedback: externally generated change is minimized,Example of positive and negative feedbacks associated with global warming,4. Spatial and temporal scale,Scale determines how we understand pattern and process Example: controls on temperature: what makes it warm or cold?,Answer depend
13、s upon temporal and spatial scale,Cloud cover and humidity (minutes to hours) Diurnal (day-night) cycles Seasonal cycles (1 year) Cyclical fluctuations due to sunspots (10-50 years) Anthropogenic contribution of greenhouse gases (10-100 years) Milankovitch orbital cycles (10,000 yrs),5. Thresholds a
14、nd time lags,Melting of ice sheets and glaciers,6. Teleconnections,7. The earth is constantly changing,Earth is an open system Change is the norm Change itself, however, has different types Steady state equilibrium Dynamic equilibrium Phase shift once tipping point (threshold) is reached Transitional states,Steady state equilibrium,Dynamic equilibrium,Phase shifts,Systems may shift to another state once a threshold is reached Can be natural or caused by humans,No analog states,Transitory states,Systems do not settle down to any dynamical equilibrium.,
