Lecture 3: Predictive Models and Trends Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Forecast

A

The public announcement that a hazardous event is likely to occur during a specified period, commonly with a statement of probability
ie. There is a 10% chance the forest will be burned unintentionally this summer, with 95% confidence
Rain is the most difficult to measure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Hindcast

A

Means of testing models, evaluate uncertainty
Uses data from past events, even if the short-term situation is monitored precisely
Usually the longer the record, the better. For weather hazards, usually try for 40+ years, for seismic hazards, may be hundreds of thousands of years
Helps define magnitude limits, boundary conditions
Need to capture events with high rates of change, or anomalous events, as these rare events may be the important ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Prediction

A

A statement regarding the occurrence of a process or outcome . May specify time, location, intensity, or magnitude.
Can be hindcast or forecast
May be considered more specific than a forecast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Warning

A

An announcement that a hazard event is happening or expected to happen in the near future in a defined regio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Watch

A

An alert issued by a government agency that weather or other environmental conditions are favourable for a hazardous event in a general region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Hazard trends: why are there increased losses in modern times?

A

We are more vulnerable

Higher population density and more infrastructure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What hazards are we becoming less vulnerable to?

A

Geological
Better warnings, building codes
As well, geological events occur over much longer time periods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Data

A

An archive of data from years of observation of past events
Current parameters related to the intensity and location of the actual hazard
Current parameters that are indirectly related
Precursor indications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Models

A

Numerical, physical (analogue)
Trends or relationships derived from past events
Complex, non-linear, chaotic relationships
Simulations, tests, hindcasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Analogue (physical) models

A

Use powder and gel that have same property as rocks (on very large scale)
Make layers, then deform it
Add magnetic grains to sand, to detect magnetic fields – put into computer to get 3D analog model
Examine the processes along a fault type
Simulate and study a specific fault
Predict where earthquakes may occur
Predict the magnitude of those earthquakes
Predict patterns in space and time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Numerical model

A

· “Algorithms”
Uses forward and inverse modeling
Typically involves significant computation
Convert (empirical) observations to (theory) equations
Make models more complex to include more factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Examples of numerical models (2)

A
  1. Dept Oceanography Storm Surge Model (Keith Thompson)

2. Dept Oceanography/Earth Sciences Geodynamics Model (Chris Beaumont)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Path to prediction

A
  1. Observation of past events (verify data, hypothesis, test hypotheses, parameterize variables, develop rules)
  2. Model (test hypothesis, hindcast, evaluate uncertainty, forecast)
  3. Prediction (alert regional and local office, continue monitoring, issue warning, update model)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are forecasts based upon?

A

Our forecasts are based on the premise that those global oceanic and atmospheric conditions which preceded comparatively active or inactive hurricane seasons in the past provide meaningful information about similar trends in future seasons
Data, models

How well did you know this?
1
Not at all
2
3
4
5
Perfectly