Dynamics of a coupled human landscape system (with New Orleans example) 27th Jan Flashcards
How do humans impact the landscape?
Effect of economic activity and changes meant to mitigate natural disasters and longer term trends
What are human dynamics dominated by?
Simplifying profit maximizing market forces and political action based on the projection of economic effect.
Research showing….(led scientists to propose..)
Research showing how human and landscape systems interact has led scientists to propose coupling of the systems.
Most scientists attribute….. but Werner and Mcnamara suggest…..
Most scientists attribute landscape processes to natural causes but Werner and Mcnamara suggest non-linear behaviour of economic and political systems are essential to modelling systems (dont follow patterns)
NON LINEARITY OF HUMAN LANDSCAPE SYSTEMS.
Werner and Mcnamara evaluated…
Economic/political systems to determine there alterations on other processes.
Werner and Mcnamara find that.. To test the hypothesis that…..Werner and Mcnamara measured…
Werner and Mcnamara find that economics are a driving force behind land alterations. To test the hypothesis that systems are coupled Werner and Mcnamara measured the interactions between the two systems as a function of non-linear and found feedback. Conclude economics is a driving force behind coupling.
Data suggests that modelling…
Data suggests that modelling should take into account free will. Cost of protection must be more than the cost of damage, free will is hard to predict. Need to determine the dynamics of past profit.
(last notes) Now this has been established….
Protection from large disasters still unresolved. Further development of coupling on multi-decadal timescale needed. Humans impact on feedback over larger time scale. Still populating land due to economic advantage= more at risk from disaster.
NEW ORLEANS MODEL (general approach)
Storm surge, Katrina, 2005.
Consider human (economic growth through shipping,tourism, scientific approach to damage mitigation) separately from landscape processes (river floods, storm surges, wetland degradation etc)
But New Orleans strongly coupled through
economic development, surface morphology, flooding and levees.
Initial model idea
Increments of 1 year in which floods (Mississippi) hurricane storm surges and damage to economic structures and construct of artificial levees are simulated.
Landscape model(new orleans)
Subsidence simulated - peak discharges chosen randomly (Mississippi) flood stage at max value.
First levee where flood stage exceeds the height, water flows through for 4 hours (matches 1850 floods)
Hurricanes chosen of different strengths. If there’s a breach lasts 8 hours (same as Katrina)
Economic model
Seven sets of agents (Home buyer,laborers, tourists, home developers. hotel developers, port owners/laborers)
through 5 markets (tourism,hotel,labor,home,port services)
Heterogeneous - employing different prediction models for each.
Where to build considered (profit) average house prices and wages calculated. Tourism matched to hotels etc.
Results of New Orleans model
Effect of increased protection filters out small frequent floods but at expense of rare large disasters. Facilitates development in disaster prone areas. Also channelization causes increasing in flood size results meaning enhanced damage from low frequency flood events.
Human landscape models are amenable to specific dynamic modelling and analysis.
Use of dynamics at middle level of hierarchy, flood routing and market sources gives realistic simulations of strongly coupled human landscape dynamics in New Orleans.
