# Presentation: 408851

## High Latitude Weather Systems- Explosively Deepening Cyclones in the Northwestern Pacific Region -

- Yoshio Asuma and Akira Yoshida
- Division of Earth and Planetary Sciences,
- Graduate School of Science,
- Hokkaido University

## Explosively Deepening Cyclones

- (Sanders and Gyakum, 1980)

## 00UTC OCT. 25, 1998
992hPa

12UTC OCT. 25, 1998
974hPa
(-18hPa/12h)

00UTC OCT. 26, 1998
968hPa
(-6hPa/12h)

- 992hPa
- 
- 12UTC OCT. 25, 1998
- 974hPa
- (-18hPa/12h)
- 
- 00UTC OCT. 26, 1998
- 968hPa
- (-6hPa/12h)

- Example of Explosively Deepening Cyclone

## Definition of Explosively Deepening Cyclone (Sanders and Gyakum, 1998)

- Data Source
- JMA Global Objectively Analyzed Dataset (GANAL)
- Analyzed Period
- October 1, 1994 – March 31, 1999 (5 Cold Seasons)
- Analyzed Region
- 20°N - 65°N, 100°E - 180°E

## Explosively Deepening Cyclone

- Rapid Deepening:
-   Higher Latitude than
-     35°N in Latitude
-   over the Ocean

- Formation:
-   over the Land and Ocean

- Three Types of Cyclone:
- Okhotsk – Japan Sea (OJ) Type
- Pacific Ocean – Land (PO-L) Type
- Pacific Ocean – Ocean (PO-O) Type

- Total : 224 cases

- Rapid Deepening:
-   Higher Latitude than
-     35°N in Latitude
-   over the Ocean

## Explosively Deepening Cyclone Type

- TOTAL:224

## OJ TYPE

- TOTAL:224
- OJ:42

- Rapid Deepening : Sea of Japan or Sea of Okhotsk
- Formation : Land

## PO-L TYPE

- TOTAL:224
- OJ:42
- PO-L:50

- Rapid Deepening : Northwestern Pacific Ocean
- Formation : Land

## PO-O TYPE

- TOTAL:224
- OJ:42
- PO-L:50
- PO-O:110

- Rapid Deepening : Northwestern Pacific Ocean
- Formation : Ocean

## Deepening Rate Frequency Distribution

- Maximum
- Deepening Rate
**OJ Type**
- Smallest
**PO-L Type**
- Medium
**PO-O Type**
- Largest

## Cyclone Type

- Cold Air Mass over the Continent
- Upper-level Trough
- Upper-level Jet
- ↓
- Cyclone Track and Deepening Rate
- (Cyclone type)

- Synoptic Environment
-                       ↓↑
- Cyclone Meso-scale Structure

**OJ Type **(Late Fall)
- Short Wave Upper-level Trough
- Short Jet Streak
- Weaker Continental Cold Air Mass
-   Extension
**PO-L Type **(Early and Late Winter)
- Zonally Stretched Jet Stream
-   (Strong Zonal Wind Component)
- Medium Continental Cold Air Mass
-   Extension
**PO-O Type **(Mid-Winter)
- Strong Jet Stream
-   (Larger Poleward Component)
- Strongest Continental Cold Air Mass
-   Extension

- Latent Heat Release

## Numerical Studies of Extreme CasesFocused on the Latent Heat Release

-  OJ TYPE
-   00UTC February 27, 1999 (1.84 Bergeron)
-  PO-L TYPE
-   18UTC February 10, 1998 (2.54 Bergeron)
-  PO-O TYPE
-   00UTC December 31, 1997 (2.96 Bergeron)

## PSU-NCAR MM5 version 3.6.1

- Horizontal Grid
-  Domain 1 : 200×160 (45 km)
-  Domain 2 : 301×271 (15 km)
- Vertical Levels : 23 Sigma level
- Initial / Boundary Conditions : JMA GANAL
- Sea Surface Temperature : Reynolds SST
- Microphysics
-  Domain 1 : Simple Ice Scheme
-    (Vapor, Cloud Water, Rain Water, Cloud Ice, Snow)
-  Domain 2 : Mixed-phase Scheme (+ Supercold Water)
- Cumulus Parameterization : Grell’s Scheme
- Sensitivity Experiments
-  CNTL Run : Full Physics
-  DRY Run : No-latent Heat Release

## OJ TYPE 

- Back Trajectory ended at 850hPa

- CNTL

- 300hPa
- Winds
- PV

- SLP
- Rain Water Path
- Precip. Water

## OJ TYPE

## PO-L TYPE

- CNTL

- Back Trajectory ended at 850hPa

- 300hPa
- Winds
- PV

- SLP
- Rain Water Path
- Precip. Water

## PO-L TYPE

## PO-O TYPE

- CNTL

- Back Trajectory ended at 850hPa

- 300hPa
- Winds
- PV

- SLP
- Rain Water Path
- Precip. Water

## PO-O TYPE

## OJ TYPE

- PO-L TYPE

- PO-O TYPE

- Effect of
- Latent Heat 	  Smallest			Medium			     Largest
- Release

## GPM

- High Latitude Weather Systems
- Examples of Higher Latitude Topics :

- Explosive Cyclones and Low Pressure Systems
- Cyclone Families and Storm Tracks
- Polar Lows
- Global Scale Frontal Structures (Polar and Arctic Fronts)
- Weather Systems over the Land and Ocean
- Transition and Re-development of Tropical Cyclones
- Cloud Bands (Streamers) over the Ocean and Lakes
- Coastal Fronts
- Orograhic Clouds and Precipitation

- TRMM :	35°N - 35°S in Latitude
- GPM :	65°N - 65°S

- (Sapporo : 43°N)

- Explosive Cyclones and Low Pressure Systems
- Cyclone Families and Storm Tracks
- Polar Lows
- Global Scale Frontal Structures (Polar and Arctic Fronts)
- Weather Systems over the Land and Ocean
- Transition and Re-development of Tropical Cyclones
- Cloud Bands (Streamers) over the Ocean and Lakes
- Coastal Fronts
- Orograhic Clouds and Precipitation

- Examples from TRMM (Nakamura and Yamamoto, 2004)

## Low Pressure Systems by TRMM

- CFAD of TRMM PR

- (Nakamura and Yamamoto, 2004)

## Cloud Bands (Cold Air Outbreaks) by TRMM

- CFAD of TRMM PR

- (Nakamura and Yamamoto, 2004)