NWS Climate Products and NWS Climate Products and Services to Support Services to Support

Decision MakersDecision Makers

Committee for Climate Analysis, Monitoring, and Services Committee for Climate Analysis, Monitoring, and Services October 30, 2007October 30, 2007

Fiona HorsfallFiona HorsfallNOAA/National Weather ServiceNOAA/National Weather Service

Climate ServicesClimate Services

OutlineOutline

• NWS Climate ServicesNWS Climate Services

• How valuable are climate forecasts?How valuable are climate forecasts?

– Climate forecast skill Climate forecast skill

– Extrapolation of long-term trends Extrapolation of long-term trends

• What’s next?What’s next?

• NWS MissionNWS Mission• Documented customer requirements forDocumented customer requirements for

– More easily understood productsMore easily understood products– Regional and local climate products and Regional and local climate products and

servicesservices

• A comprehensive operations manualA comprehensive operations manual• PartnershipsPartnerships• Climate record stewardshipClimate record stewardship

NWS CLIMATE SERVICES

NWS has a vast and robust Climate Services Program

• Extensive staff trainingExtensive staff training– Climate variability and changeClimate variability and change– Data stewardshipData stewardship– Customer serviceCustomer service

• Standardized web pagesStandardized web pages– Data web toolsData web tools– Copious help information for customersCopious help information for customers

• New forecast productsNew forecast products– Local 3-Month Temperature Outlook (L3MTO), Local 3-Month Temperature Outlook (L3MTO),

with others coming soonwith others coming soon

NWS CLIMATE SERVICES

NWS has a vast and robust Climate Services Program

Local 3-Month Temperature Local 3-Month Temperature Outlook - Outlook - L3MTOL3MTO

L3MTOL3MTO

L3MTOL3MTO

L3MTOL3MTO

L3MTOL3MTO

L3MTOL3MTO

L3MTOL3MTO Formats Formats

L3MTOL3MTO Probability of ExceedanceProbability of Exceedance

Why is Why is L3MTOL3MTO Useful? Useful?

• If large-scale forecast has skill, uses If large-scale forecast has skill, uses forecast – downscaled to stationforecast – downscaled to station

• Adjusts forecast to take into account local Adjusts forecast to take into account local climate (micro climates)climate (micro climates)

• If no skill in large-scale forecast, adjusts If no skill in large-scale forecast, adjusts local climatology to incorporate local local climatology to incorporate local trendtrend

A Quick Note about A Quick Note about Climate Forecast SkillClimate Forecast Skill

What do we know? What do we know?

• There are important There are important long-term trends in long-term trends in the mean temperature and precipitationthe mean temperature and precipitation climates of North America.climates of North America.

• Primary sources of skill for North AmericaPrimary sources of skill for North America– TrendTrend– ENSO (El NiENSO (El Niño-Southern Oscillation)ño-Southern Oscillation)

Variations of the Earth’s surface temperature

Variations of the Earth’s surface temperature

Global Global meanmean14.0°C14.0°C

Trenberth (2004)

Weak TrendsWeak Trends

Livezey et al, 2007

a) 30-Year Hinge Temperature Trend (°C/30 yrs) - JFM

b) 30-Year Hinge Precipitation Trend (cm/30 yrs) - OND

<-2 -2 to -1.3 -1.3 to -0. 7 -0.7 to -0.4 -0.4 to -0.2 -0.2 to 0.2

0.2 to 0.4 0.4 to 0.7 0.7 to 1.3 1.3 to 2 >+2

<-11.4 -11.4 to -7.6 -7.6 to -4.6 -4.6 to -2.3 -2.3 to -0.8 -0.8 to 0.8

0.8 to 2.3 2.3 to 4.6 4.6 to 7.6 7.6 to 11.4 >11.4

Strong TrendsStrong Trends

Forecast SkillForecast Skill

• Heidke Skill ScoreHeidke Skill Score

• % improvement over expected% improvement over expected• Count EC (equal chances) as a hitCount EC (equal chances) as a hit• Forecasts become usable with score Forecasts become usable with score

> +25> +25• Smaller cost/loss ratio – can use lower scoreSmaller cost/loss ratio – can use lower score

Hits: Forecasts correctExpected: ClimatologyTotal: Total forecasts

Hits – ExpectedTotal - Expected

3-Month Temperature Forecast SkillNon-ENSO Years

Skill

Livezey and Timofeyeva, 2007

3-Month Precipitation Forecast SkillNon-ENSO Years

Skill?

Livezey and Timofeyeva, 2007

Skill - A little in places

Temperature & Precipitation SkillTemperature & Precipitation SkillStrong ENSO YearsStrong ENSO Years

Skill Skill

Livezey and Timofeyeva, 2007

A Quick Note about A Quick Note about Global Climate ChangeGlobal Climate Change

• In order to credibly project future scenarios of In order to credibly project future scenarios of high-impact weather-related events, a model high-impact weather-related events, a model must credibly treat them in the past must credibly treat them in the past

• Existing climate models cannot reproduce Existing climate models cannot reproduce weather scenarios adequately over the recent (30-weather scenarios adequately over the recent (30-year) historical recordyear) historical record

• Thus they cannot credibly produce future Thus they cannot credibly produce future weather scenarios of other than the gross weather scenarios of other than the gross geographic and seasonal distribution of mean geographic and seasonal distribution of mean surface temperaturesurface temperature

• This applies to all spatial scales, including This applies to all spatial scales, including regional regional

Climate Model CapabilitiesClimate Model CapabilitiesDJF JJA

? ? ?

NOAA Online Weather Data NOAA Online Weather Data NOWDataNOWData

• Data query Data query system for basic system for basic climate statisticsclimate statistics

• 30+ years30+ years

• 3,800 surface 3,800 surface observing observing stations (non-stations (non-airport)airport)

• Conterminus Conterminus U.S., AK, HI, PR, U.S., AK, HI, PR, USVI, GuamUSVI, Guam

Ref: Bob Leffler

NWS CLIMATE SERVICES

• The Training Program is available at Climate Services Professional Development Series (PDS)

http://www.nws.noaa.gov/om/csd/pds/index.shtml

• Instructional Components of Climate Services PDS available to non-NWS users:– Online tutorials– Webcasts – Teletraining

NWS CLIMATE SERVICESTraining

Downloadable free NWS fact sheetsDownloadable free NWS fact sheets

Available at: http://www.weather.gov/os/brochures.shtml

NWS Climate ServicesNWS Climate Services

Will be Precipitation

Will be Precipitation

Local 3-month Precipitation Outlook (L3MPO)

NWS Climate ServicesNWS Climate Services

Will be Precipitation

Will be Precipitation

For Example:For Example:

• Pacific Islands – Sea-level forecasts Pacific Islands – Sea-level forecasts

• Florida – Forecasts for “storminess” or the Florida – Forecasts for “storminess” or the number of storms expected to occur during number of storms expected to occur during the dry seasonthe dry season

• Baltimore, Maryland – Forecast for the Baltimore, Maryland – Forecast for the likelihood of a major winter snow eventlikelihood of a major winter snow event

NWS Climate ServicesNWS Climate Services

3-Month Outlook of Local El Ni3-Month Outlook of Local El Niñño/La Nio/La Niñña Impacts a Impacts (3MOLEI)(3MOLEI)

• Outlooks based on local El Niño/La NiñaEl Niño/La Niña signal

SummarySummary

• NWS has robust Climate ServicesNWS has robust Climate Services

• NWS local forecast products provide NWS local forecast products provide services to the publicservices to the public

• Climate forecasts offer some skill, but not Climate forecasts offer some skill, but not perfectperfect

• We are working on new products and We are working on new products and servicesservices

• Contact local forecast offices for more Contact local forecast offices for more informationinformation