Intense surface cyclone activity in the arctic during the 2005 06 and 2006 07 cool seasons
Download
1 / 56

Intense Surface Cyclone Activity in the Arctic During the 2005-06 and 2006-07 Cool Seasons - PowerPoint PPT Presentation

Intense Surface Cyclone Activity in the Arctic During the 2005-06 and 2006-07 Cool Seasons Brian Silviotti, Lance F. Bosart, and Daniel Keyser Department of Earth and Atmospheric Sciences University at Albany, Albany, New York 33 rd Northeastern Storm Conference 14-16 March 2008

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

Intense Surface Cyclone Activity in the Arctic During the 2005-06 and 2006-07 Cool Seasons

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Intense Surface Cyclone Activity in the Arctic During the 2005-06 and 2006-07 Cool Seasons

Brian Silviotti, Lance F. Bosart, and Daniel Keyser

Department of Earth and Atmospheric Sciences

University at Albany, Albany, New York

33rd Northeastern Storm Conference

14-16 March 2008


Motivation

Major Arctic Shipping Routes

  • Arctic not studied often

  • Intense arctic cyclones

    pose economic hazards,

    especially to shipping

Source: www.hofstra.edu


Purpose

  • Establish a limited track climatology

  • Compare cyclone mergers and

    nonmergers

  • Present a case study of a cyclone merger event


Methodology

  • Definitions

    • Cool season – October 1 to March 31

    • Arctic – poleward of 50°N

    • Intense cyclone – central pressure ≤ 980 hPa

  • Subjectively analyzed maps

    • Genesis/lysis time

    • Position and track

    • Central pressure

    • Merging


Data

  • Maps

    • NH MSLP and 1000-500 hPa thickness

    • NH dynamic tropopause (DT) potential temperature and wind

  • Datasets

    • GFS 0.5/1.0° analysis

    • NCEP/NCAR Reanalysis

  • Sources

    • Ron McTaggart-Cowan online GFS animation builder

    • University at Albany DEAS archive room

    • CDC interactive plotting and analysis web page


2005-06 Cool Season 300 hPa Height Mean and Anomaly

CI = 100m

CI = 10m

Source: www.esrl.noaa.gov/psd


2006-07 Cool Season 300 hPa Height Mean and Anomaly

CI = 100m

CI = 10m

Source: www.esrl.noaa.gov/psd


2005-06 Cool Season Storm Tracks

Oct/Nov

Dec/Jan

Feb/Mar

  • 50 Storms

  • Oct/Nov: 20

  • Dec/Jan: 21

  • Feb/Mar: 9


2006-07 Cool Season Storm Tracks

Oct/Nov

Dec/Jan

Feb/Mar

Case Study

  • 96 Storms

  • Oct/Nov: 25

  • Dec/Jan: 47

  • Feb/Mar: 24


Merger Locations - By Month (2005-07)

Oct/Nov

Dec/Jan

Feb/Mar

Case Study

  • 44 Mergers

  • Oct/Nov: 11

  • Dec/Jan: 22

  • Feb/Mar: 11

Arctic/Arctic Mergers

23

Arctic/Mid-latitude Mergers

21


Merger Locations – By Strength (2005-07)

970 – 980 hPa

960 – 969 hPa

950 – 959 hPa

< 950 hPa

Case Study

  • 44 Mergers

  • 970-980 hPa: 16

  • 960-969 hPa: 17

  • 950-959 hPa: 9

  • < 950 hPa : 2


Mergers vs. Nonmergers


Case Study

  • Example of a cyclone merger event

  • Occurred in Central Pacific for

    11 Feb. 2007 - 19 Feb. 2007

  • Two surface cyclones and three positive potential vorticity (PV) anomalies merged


300 hPa Height Mean and Anomaly for 11 Feb. 2007 - 19 Feb. 2007

CI = 50m

CI = 15m

Source: www.esrl.noaa.gov/psd


Case Study – Surface Lows

Feb. 2007


Case Study – PV Anomalies

Feb. 2007


Case Study – PV Anomalies and Surface Lows

Feb. 2007


11 Feb. 2007 12 UTC DT Potential Temperature, Wind

C

B

A


12 Feb. 2007 00 UTC DT Potential Temperature, Wind


12 Feb. 2007 12 UTC DT Potential Temperature, Wind


13 Feb. 2007 00 UTC DT Potential Temperature, Wind


13 Feb. 2007 12 UTC DT Potential Temperature, Wind


14 Feb. 2007 00 UTC DT Potential Temperature, Wind


14 Feb. 2007 12 UTC DT Potential Temperature, Wind

AB

C


15 Feb. 2007 00 UTC DT Potential Temperature, Wind


15 Feb. 2007 12 UTC DT Potential Temperature, Wind


16 Feb. 2007 00 UTC DT Potential Temperature, Wind


16 Feb. 2007 12 UTC DT Potential Temperature, Wind

AB

D

C


17 Feb. 2007 00 UTC DT Potential Temperature, Wind


17 Feb. 2007 12 UTC DT Potential Temperature, Wind


18 Feb. 2007 00 UTC DT Potential Temperature, Wind

ABD


18 Feb. 2007 12 UTC DT Potential Temperature, Wind


19 Feb. 2007 00 UTC DT Potential Temperature, Wind


19 Feb. 2007 12 UTC DT Potential Temperature, Wind


15 Feb. 2007 12 UTC Sounding from Akita, Japan

Source: www.weather.uwyo.edu


11 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


12 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


12 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


13 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


13 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


14 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


14 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


15 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


15 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


16 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


16 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


17 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


17 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


18 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


18 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


19 Feb. 2007 00 UTC MSLP, 1000-500 hPa Thickness


19 Feb. 2007 12 UTC MSLP, 1000-500 hPa Thickness


Conclusions: Track Climatology

  • On average there are 10-15 intense arctic cyclones per month

    • High intraseasonal and interannual variability

  • Most frequent over Gulf of Alaska/Aleutians and North Atlantic/East Arctic Oceans

    • Clustering near end of well known storm tracks


Conclusions: Mergers and Case Study

  • All mergers occur poleward of 50°N: mid-latitude storms move into arctic due to amplified pattern

  • Mergers typically occur when southern storm is fairly well developed

    • Arctic PV anomaly acts on atmosphere with already high low-level vorticity: expedites further vorticity growth

    • In arctic/mid-latitude mergers, arctic storm provides extra “kick” in the form of vorticity


Further Research

Annual Cyclone Density

  • AO, NAO, PNA related to arctic storm activity

  • Nature of Pacific Jet vs. Atlantic Jet

  • Oceanic diabatic effects

  • Role of arctic PV anomalies

N. America

Source: Hakim and Canavan (2005)


Questions/Comments?


ad
  • Login