u.s. climate reference network developments research-to-operations: midway to noaa’s model climate...
TRANSCRIPT
U.S. Climate Reference Network Developments
Research-To-Operations:
Midway To NOAA’s Model Climate Monitoring Network
Presentation for the
Committee for Climate Analysis, Monitoring, and Services
Dr. Michael R. Helfert
NOAA/NESDIS
National Climatic Data Center
May 3, 2005
The Question, Principles, & Network• Performance Measures, Nat’l & Regional
• Sensor Suites/Instruments
• Site Survey Primer
• Cross-Network Transfer Functions
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• Products and Product Development
• Where’s the Information?
• Where We Want To Be in 2010.
Climate Reference Network
How has the climate of the U.S. changed over the past 50 years on national,
regional and local levels?
Just what is the Climate Reference Network?An observing system that 50 years from now can, with
the highest degree of confidence, answer the question…
U.S. Climate
Reference Network
National Climatic Data Center
Basic Principles of the CRN
• U. S. Benchmark Network for Temp/Precip• Adheres to the “Climate Monitoring Principles” • Satisfy Requirements of Observing Systems• Anchors the U. S. Historical Climate Network (HCN)• Strong Climate Science & Research Component• Long-Term Stability of Observing Site (50+ years)• Sensors Annually Calibrated to Traceable Standards • Network Performance Monitoring - Hourly and Daily• Climatically representative & stable station sites
using rigorous, systematic site selection
Program Status• 70 Commissioned Stations operational of 114 planned.• Data and Metadata for all commissioned sites on-line.• FY05 USCRN budget 0%; 50% funding recovered for O&M.• Revised Performance Measures necessitated (T&P).• FY06-08: 42 stations planned, budgets pending.• 108 of the 114 station sites have been identified; 90 approved; 18 in review; last 6 site surveys underway.
• Outyr interest – AL, PA, CA, NC, GCOS, IPY, & DOD.
• FY2005 Non-CONUS stations to HI & AK (GCOS).• Outyr GCOS deploys possible: Great American Cordillera,
Caribbean, Africa, IPY Arctic Ring; Antarctic region, Europe, Equatorial & WPAC, Himalayas, 7 Sisters Rgn, Kamchatka-Kuriles.
U.S. Climate
Reference Network
Annual Maintenance Visit• Exchange datalogger• Exchange one PRT• Exchange one aspirated shield fan• Exchange anemometer• Exchange pyranometer• Calibrate precipitation gauges• Complete maintenance checklist• Take compass-platte photographs• Bring station up to current configuration
U.S. Climate
Reference Network
114 CONUS Geographic Locations Required
• Captures 98% of variance in monthly temperature,
95% in annual precipitation for CONUS.• Average annual error <0.1ºC for temperature,
<1.5% for precipitation• Trend “errors” <0.05ºC per decade• IPCC: projects warming of 0.1-0.3ºC/decade and
precipitation changes of 0–2%/decade for CONUS.
Performance Measures U.S. Climate
Reference Network
Determine the Actual Long-term Changes in Temperature and Precipitation of the Contiguous U.S. (CONUS)
Uncertainty of Twentieth Century CONUS precipitation trends is large (5% of total annual precipitation), as calculated trends range from 38.1 to 77.2 mm/Century. Goal is to reduce USCRN trend uncertainty from 19.2 (FY04) to 7.7 (FY08) mm per century (reduction equates to 40% of water in Great Lakes).
Current CONUS temperature trend uncertainty (0.1o C per century, FY04) will be further reduced, enablingthe capture of any acceleration or deceleration of trends now estimated to be increasing by about 0.2o C per decade since mid-1970s.
FY2005 Target: Capture more than 96.9% and 91.1% of the temperature and precipitation trends.
April 05 Actual
Planned CRN Stations
(September 2008)
Regional Impact
Preliminary analysis (Dr. Bomin Sun)Significance level of a linear temperature trend (1951-2002) Red: upward trend Blue: downward trend
National Climatic Data Center
Minimum Observing Requirements
• Primary MeasurementsAir Temperature Precipitation Accumulation
• Supporting MeasurementsWind SpeedGlobal Solar RadiationGround Surface (Skin) Temperature
---------------------------------------------------------------------------Relative Humidity Soil Moisture & Soil Temperature Barometric Pressure
Sensor Suites/Instruments
National Climatic Data Center
Sensor Suites/Instruments
Geonor and Small DFIR w/Single Alter
National Climatic Data Center
Sensor Suites/InstrumentsPrimary and Supporting Sensors
Sensor Suites/InstrumentsInhomogeneity Adjustment Issue
Site Survey Primer
U.S. Climate
Reference Network
Kestersen CA site looking north from south. Road along canal is elevated about 5 feet. Standing in Bureau of Reclamation land.
Controlled Superfund Site for next 200+ yrs.
Major Principles of Climate Station Siting
• Site is representative of climate of region.
• Minimal microclimatic influences.
• Long-term (50-100 year) land tenure
• Minimal prospects for human development
• Avoids agriculture, major water bodies, major forested areas, basin terrain.
• Accessible for calibration & maintenance.
• Stable Host Agency or Organization.
• Follows WMO Climate Station Siting Guidelines
WMO Standards
WMO Guide to Climatological Practices "The Siting of Climatological Stations" Chapter 4 paragraph 2.4, pages 45-50.
CRN Site Information Handbook, CRN Survey Checklist, CRN Scoring Sheets.
-------------------------------------------------------------------WMO Initial Guidance To Obtain Representative
Meteorological Observations At Urban SitesTD-1250, 47 pp. 2004.
Site Survey PrimerAvoiding Microclimates
Pinnacles RAWS site looking to east from west. Uncontrollable burns on 2-5 yr cycle. High creosote chaparral environment with dry grasses understory.
Site Survey Primer
Avoiding Microclimates
Schwardt Lab Site,40m distant, height 8mMinimum of 80 mtrs separation is needed.
Rock Springs, Emergin Corn Crop <10 m away. Crop annually rotates w/Soy & Wheat.180 mtrs separation from non-irrig agricultureis required
Pacific Northwest Federal Area,
co-location with Cooperative Station (HCN)
USCRN StationsSeptember 2004 (69 stations)
Installed Paired Locations
Installed Single Locations
Planned USCRN Stations at end of 2008 (114* stations)
* Does not Include Alaska, Canada, Hawaii, & GCOS stations
Installed Paired Locations
Installed Single Locations
As of April 26, 2005
Cross-Network Transfer FunctionsU.S. Climate
Reference Network
Cooperative Observer Network (~10,000 Stations)
USCRN Site Survey 10/19/04 Pasture 3 Site
USHCN Site, 1909, at Cottonwood Headquarters(also one of Helmut Landsberg’s 21 RCS’s)
RAWS Site
CRN Site
COOP Site
Dinosaur National Monument CRN Site w/co-locations
Installed Pair (14)
Installed Single (59)
Alaskan & Canadian Stations (3)
not included in portrayal.
USCRN Network Configuration
As of May 4, 2005
(May 4, 2005)
CRN Data Management Activities:Flow of Data from Station To Users
NCDC
Communications Network
Field Sites
Instrument Suite
Communications Device
Processing Unit
Internet
User Community
Access
Ingest
Processing
Quality Control
Maintenance Notification
Maintenance Provider
Flagged-Data Archive
Raw-Data Archive
online
offline
PRODUCTS• Ingesting into routine Drought Monitoring and
Climate Monitoring activities & products at NCDC
• Prelim Normals (3-Yr) being used for older CRN’s
• Transfer functions for up to 3-Yr POR being run on routine basis. Updated each successive yr.
• Forthcoming Energy/Agriculture Applications by using Traditional vs 5-min/hourly corrected HDD/CDD & mean weighted max/min T’s for new LCD. Both LCD portrayals will be user accessible.
• CRN Data being now used in TempVal & PrecipVal (Primary NCDC QA/QC Routine for ASOS, COOP, MMTS, ISD, etc. – in other words, it’s already there, you just don’t see it…)
Pushing Too Fast – an Experimental Product with Insufficient POR and Insufficient Station Density:
Tmax Anomaly of July 2004
ºC
USCRN CONUS Deployments
With Network Co-locations*
*Colocations witin 10 km.
Data as of April 26, 2054
No Co-location Known
Coop or HCN Co-located Coop + Another Network Co-located (SURFRAD, RAWS, NADP, etc.)
NADP Co-located
RAWS/SCAN Co-located
SURFRAD Co-located
Estimating CRN T & P Normals
1. Places current USCRN observations into historical perspective for operational climate monitoring activities.
2. Allows inter-network transfer function determination (e.g., CRN <–> COOP) 3. Provides stable & leveraged data core for
NOAA & other agency climate products
STABLE, HIGH-CONFIDENCE CRN Normals require a min of a 5 yrs POR; 10 yrs POR desired.
Shorter POR’s produce poor-quality, low-confidence transfer functions & normals. Definitely not one of our goals…
USCRN Estimated Temperature Normals Product and Error Ranges, 1 – 3 yrs Period-of-Record
Example, October T normals, ºCelsius
Stations Estimated normalsTmin Tmax Tmean
ErrorsTmin Tmax Tmean
Yrs of data
Asheville NC
6.0 19.3 12.7 0.24 0.22 0.17 3
Old Town ME
1.4 13.4 7.3 0.40 0.22 0.25 2
St. Mary MT
0.5 10.4 5.3 0.44 0.32 0.37 1
Web Access
USCRN Homepage URL:
http://www.ncdc.noaa.gov/oa/climate/uscrn/
5-Yr CRN Vision• Sufficient CRN stations deployed ( ~ 114) for capture of CONUS
National Climate T & P Signals for stations with 5-yr POR for normals & extremes estimation (high-confidence products).
• Inter-network (HCN, Coop, SCAN, SNOTEL, RAWS) transfer functions give increased, homogeneous density coverage, and allow CRN to “steal time” backwards (integrated normals).
• Inter-network (esp. using CRN + ~615 “best” HCN-M) transfer functions determination will extend high-confidence T & P
normals sufficiently as to allow Regional Climate T&P Signal determinations for all 11 U.S. Standard Climate Regions.
• Sufficient CRN data stream & confidence supports broad scientific analyses and debate of climate trends, envelopes, and extremes.
• CRN 5-minute data on-line within one hour of receipt at NCDC.
• CRN data and metadata continue to have full public access.