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Fundamentals of Simulation Modeling in the Hydrologic Sciences:

Introduction

Alejandro Flores, Ph.D.Fall 2010

Introduction

What is a model?

Why do we need/want to use models in hydrology?

What is a model?

A model is a mathematical abstraction of reality: Requires simplification of processes Often draw analogies between processes and

existing mathematical methods and formulae Often requires “parameterization”

A model is nothing more than a set of equations that collectively represent one or more hypothesis/hypotheses

What is a model?

A model is NOT… A perfect representation of reality (although

sometime it’s convenient to assume it to be) A substitute for observation

This is an Airbus A380

This is a model of an Airbus A380

This is another model of an A380

This is another model of an A380

Yet another model of an A380…

Just one more for good measure

So, then…

What do all these models have in common?

How do they differ? What is the purpose of each? Who is the audience? What is the balance between simplicity and fidelity?

Why do we model in hydrology?

What are some reasons we need to model in hydrology?

What are some tradeoffs between fidelity/realism and simplicity?

Who are our audiences?

What are the consequences of inaccuracy for each audience?