# Presentation: 420664

## NWS Alaska Region: Climate, THORPEX and the IPY

**NWS Alaska Region: Climate, ****THORPEX and the IPY**

- THORPEX Workshop
- January 19, 2006
- James Partain, Chief
- Environmental & Scientific Services Division
- NOAA NWS Alaska Region

## NWS Alaska Region – Climate Challenges

- Climate change in Alaska is _WAY_ beyond academic:
- Decades-old warming at locations all across Alaska
- Greatly reduced extent *and* thickness of multi-year sea ice
- Later freeze-up in Fall and earlier break-up in Spring
- Glaciers retreating, Permafrost melting with attendant issues
- For us, debate over *cause* of warming is moot: NOAA’s *weather* customers are impacted on a daily basis – they are looking to us for expertise!

## Climate Impacts on Service Programs in NWS Alaska Region

- Aviation – more frequent icing, IFR conditions; aviators in bush still operating on old assumptions
- Public - more frequent “high amplitude” weather episodes (e.g. mid-winter thaws, coastal storms, windstorms, heavy precip)
- Marine – more frequent high-impact events, esp. in areas of sea-ice retreat
- Wildfire - more variable regime-dependent fuel-moisture conditions

## Climate Impacts on Service Programs in NWS Alaska Region (cont)

- Hydrology – greater variability in river volume & depth and related flooding and erosion; ice-dammed glacier lake releases
- Volcanic Ash – resuspension of relic ash from Katmai complex in Sept. 2003 led to redefinition of volcanic ashfall “event”
- Tsunami – sea-level rise may have eventual impacts

## Slide 5

## Climate Science Needs - Observations

- Observations form the backbone of forecasts and warnings:
- vertical, spatial and temporal distributions of moisture, temperature, and kinetic energy equal “weather”
- the need to know what’s really happening (to calibrate both our brains and our models)
- ...which results in a heavy dependence on surface (land and marine) and space-based observations:
- remotely-sensed (e.g. profilers, radars, radiometers, scatterometers, GPS-moisture)
- and in-situ (e.g. weather observations, buoys, weather cameras).

## Climate Science Needs - Models

- In Alaska, guidance from numerical models is especially critical for forecasts & warnings beyond 6-hours
- NWS atmospheric models generally do worst at the poles.  Alaska in particular suffers with poor model quality due to its position within and downstream of one of the most data-sparse, yet dynamic weather regimes on the planet
- Observing system tests (e.g. PACJET, THORPEX, WSR) have proven the value of observations to improving our models (esp. vertical atmospheric observations, plus land/ocean observations of antecedent conditions)
- Improved models lead to improved and more confident services by forecasters and decision-makers
- THORPEX!

## Slide 8

## Slide 9

## Example:  the Bering Sea Storm, Oct. 2004

- One of the greatest short-term weather impacts of climate change are for coastal storms and attendant erosion
- Later freeze-up, less extent and thinner sea-ice, combined with loss of coastal permafrost, is a recipe for erosion from normal Fall storms
- Impacts magnified by greater wave size due to increased open-water fetch
- Customers need forecast Accuracy and Lead Time and, in this case, got it (well-assimilated observations, good model runs, good resultant diagnosis & products, and excellent response)

## A residence in Shishmaref – after the storm

## Thanks to Dave Parsons for the following slides (Imitation is the sincerest form of flattery :-)

## THORPEX, the International Polar Year (IPY), and Alaska

- National Center for Atmospheric Research
- Co-chair, North American THORPEX Regional Committee
- Boulder, Colorado

## IPY

- Previous IPY years were 1882-83; 1932-33; and 1957-58.
- Previous IPYs investigated geophysical processes in the polar latitudes.
- IPY: 2007-08 will include investigations of biological, chemical, and geophysical processes, and societal/economic assessments and impacts.
- IPY: 2007-08 will also encompass the two-way interaction between polar and sub-polar latitude regions.
- Intensive observing period from 1 March 2007 to 1 March 2009, leading to a legacy of multi-disciplinary observational networks, and observatories.
- Further details on the planning for the International Polar Year can be found at www.ipy.org

## IPY Core Objectives

*To determine the present environmental status of the polar regions by quantifying their spatial and temporal variability.*
*To quantify and understand, past and present environmental and human change in the polar regions in order to improve predictions.*
*To advance our understanding of polar-global teleconnections on all scales, and of the processes controlling these interactions.*
*To investigate the unknowns at the frontiers of science in the polar regions.*
*To use the unique vantage point of the polar regions to develop and enhance observations studying the Earth’s inner core, the Earth’s magnetic field, geospace, the Sun and beyond.*

## THORPEX and the IPY

**International Polar Year (IPY):**
- 	**Assess and predict the state of the polar regions (03/2007-02/2009)**
- 	Fixed time period (3/2007 to 2/2009)
- 	Highly multidisciplinary
- 	Study areas of strongest climate change impact
- 	Comprehensive research in both polar regions
- 	A polar program with interest in global processes
- 	Major (“once in a lifetime”) international program under the WMO and ICSU
- 	International support and NOAA and NSF interest
**THORPEX:**** **
- 	**Accelerate improvements in skill/utility of 1-14 day weather forecasts**
- 	Long-term (10-yr) ***global ****research program*
- 	Multidisciplinary
- 	Strong link with operational Numerical Weather Prediction (NWP) centers and their 	substantial resources
- 	A global program with interest in the polar regions
- 	Major (“once in a lifetime”) international program under WMO
- 	Broad international participation with growing interagency interest in the US
*	*
***	******THORPEX HAS BEEN PROPOSED BY THE WMO TO BE THE WEATHER COMPONENT OF IPY AND A MAJOR ORGANIZING FACTOR FOR IPY WEATHER AND CLIMATE STUDIES***

## THORPEX-IPYPart I: “Practical” Problems

**THORPEX/IPY will assess the skill in the prediction of polar to global high impact weather events for different observing strategies in higher latitudes.**
**THORPEX/IPY will assess and seek to improve the quality of operational analyses and research reanalyses products in the polar regions (through utilizing IPY measurements and efforts to better utilize relevant satellite measurements).**
**THORPEX/IPY will make recommendations on the design of the Global Observing System in polar regions for weather prediction and climate monitoring.**

## THORPEX-IPYPart II: High resolution modeling

**THORPEX/IPY will develop, test and refine coupled high resolution models designed to simulate and predict conditions of the polar earth system.**
- To increase knowledge of the polar coupled earth system.
- To understand the limitations of coarse resolution models and improve model physics.
- To provide a legacy modeling system
- To improve analyses and subsequent predictions.

## THORPEX Interest in the IPY Part #3 IPY theme #3 (of 6): “Advance our understanding of polar - global interactions by studying teleconnections on all scales.”THORPEX goal of advancing understanding and prediction of regional to global influences on the predictability of high impact weather

## Global Circulations and Polar Regions

- Organized, deep tropical convection over the Pacific consistently and significantly impacts Alaska and other regions in the Arctic through Rossby waves and other circulations.
- Climate and NWP model predictions of tropical convection are extremely difficult.
- Prediction in the Arctic is sensitive to how well conditions are depicted over the Pacific, especially for these convective events.
- These convective events are poorly observed from space (clouds and satellite’s Achilles heal).
- High resolution, limited area models are highly sensitive to  these lateral boundary conditions. A problem for the proposed high resolution simulations over the Arctic for IPY.

## THORPEX Pacific Predictability Workshop, Seattle6 to 7 June 2005

- 50 researchers, forecasters and operational scientists from the US, Canada, Taiwan, Japan, and the EU met to discuss a THORPEX Pacific field campaign during the IPY.
- The tropical convection to global “teleconnection” problem was selected as the area of focus.
- International resources will be leveraged (local predictions of typhoons, ET storms etc are important to the Pacific rim)
- August through November 2008 is the proposed period of operation. Measurements primarily in the eastern Pacific.