wolf and woolf 2006 paper discussion
DESCRIPTION
Presentation by Irma Caraballo AlvarezTRANSCRIPT
Waves and Climate Change in the North-East Atlantic
by Judith Wolf and David K. Woolf
Presented by: Irma Caraballo Álvarez
October 4, 2012
Introduction
Wave models
Results
Discussion
Outline
Wave height increase Last 25 years Up to 14m in January 1993 Observed by
Buoys Ships Satellite altimetry
TOPEX/Poseidon
Introduction
North Atlantic Oscillation (NAO)
Icelandic Low
Azores High
+NAO
Stronger westerlies
Introduction
Introduction
Figure 1. NAO from NOAA (http://www.climatewatch.noaa.gov/wp-content/uploads/2011/03/ao-nao2_pos_vs_neg.jpg).
Possible reasons
Increase in winds
Increase in storminess
Storminess variations in decadal scales
Introduction
Usefulness
Interpret data
Study impacts of climate change
Investigate physical explanations
Extrapolate the model
Wave Models
Wave Models
Figure 2. Mean atmospheric conditions for January 1993. Coloured shading/contours is wind speed in m/s, arrows indicate direction of flow.
Data ECMWF ERA-40 re-analysis model, January
1993 NCEP/NCAR re-analysis model
Validation TOPEX/Poseidon Buoys
Wave Models
Variables
Strength of the westerlies
Frequency of storms
Intensity of storms
Strom tracks
Storm translation speeds
Wave Models
Wave Models
Figure 3. Idealized storm with maximum wind speed 10m/s.
Wave Models
Table 1. Features of the Storm Varied in the Experimentsa.
Feature Low Medium High
Frequency (month -1) 3 6 9
Intensity (m s-1) 10 15 20
Relative Strength 0.5 1 1.5
Direction ENE NE NNE
Speed (km h-1) 25 50 100 aValues in bold are the "standard" case.
Results Storm frequency
Storm intensity
Relative strength of westerlies
Storm track
Storm translation speed
Figure 4. Effects of the variables on wave height. Red crosses = monthly maximum, blue squares = monthly mean.
Is it possible to predict storms using this model?
Can the model be used in other regions?
Is NAO and storm frequency related to global warming?
Discussion
The End