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Monitoring the State of Watchington Monitoring the State of Watchington Kelly Redmond Western Regional Climate Center Desert Research Institute Reno Nevada University of Washington Scoping Workshop June 15, 2007 So, you wanna run a climate network? A Checklist Guidelines prepared for CIRMOUNT Mountain Climate Network, and for NPS Climate versus Weather Climate measurements require consistency through time. Network Purpose Anticipated or desired lifetime. Breadth of network mission (commitment by needed constituency). Dedicated constituency—no network survives without a dedicated constituency. Site Identification and Selection Spanning gradients in climate or biomes with transects. Issues regarding representative spatial scale—site uniformity versus site clustering. Alignment with and contribution to network mission. Exposure—ability to measure representative quantities. Logistics—ability to service station (Always or only in favorable weather?). Site redundancy (positive for quality control, negative for extra resources). Power—is AC needed? Site security—is protection from vandalism needed? Permitting often a major impediment and usually underestimated. Running a network - 2 Station Hardware Survival—weather is the main cause of lost weather/climate data. Robustness of sensors—ability to measure and record in any condition. Quality—distrusted records are worthless and a waste of time and money. High quality—will cost up front but pays off later. Low quality—may provide a lower start-up cost but will cost more later (low cost can be expensive). Redundancy—backup if sensors malfunction. Ice and snow—measurements are much more difficult than rain measurements. Severe environments (expense is about two–three times greater than for stations in more benign settings). Communications Reliability—live data have a much larger constituency. One-way or two-way. Retrieval of missed transmissions. Ability to reprogram data logger remotely. Remote troubleshooting abilities. Continuing versus one-time costs. Back-up procedures to prevent data loss during communication outages. Live communications increase problems but also increase value. Running a network - 3 Maintenance Main reason why networks fail (and most networks do eventually fail!). Key issue with nearly every network. Who will perform maintenance? Degree of commitment and motivation to contribute. Periodic? On-demand as needed? Preventive? Equipment change-out schedules and upgrades for sensors and software. Automated stations require skilled and experienced labor. Calibration—sensors often drift (climate). Site maintenance essential (constant vegetation, surface conditions, nearby influences). Typical automated station will cost about $2K per year to maintain. Documentation—photos, notes, visits, changes, essential for posterity. Planning for equipment life cycle and technological advances. Maintaining Programmatic Continuity and Corporate Knowledge Long-term vision and commitment needed. Institutionalizing versus personalizing—developing appropriate dependencies. Running a network - 4 Data Flow Centralized ingest? Centralized access to data and data products? Local version available? Contract out work or do it yourself? Quality control of data. Archival. Metadata—historic information, not a snapshot. Every station should collect metadata. Post-collection processing, multiple data-ingestion paths. Products Most basic product consists of the data values. Summaries. Write own applications or leverage existing mechanisms? Funding Prototype approaches as proof of concept. Linking and leveraging essential. Constituencies—every network needs a constituency. Bridging to practical and operational communities? Live data needed. Bridging to counterpart research efforts and initiatives—funding source. Creativity, resourcefulness, and persistence usually are essential to success. Running a network - 5 Final Comments Deployment is by far the easiest part in operating a network. Maintenance is the main issue. Best analogy: Operating a network is like raising a child; it requires constant attention, and the kid never leaves home. Source: Western Regional Climate Center (WRCC) Cooperative network Operator: National Weather Service Archive: National Climatic Data Center, many others Measurement interval: Daily Record length: 100+ years Manual Max temp, min temp, precipitation, snowfall, snowdepth Reporting interval: Monthly, many now daily via Weathercoder and SHEF Purpose: General climate of the United States Approximately 130 stations if all are reporting. Biased toward where people live and work, not many at high elevations. Not in the wettest places. Are in the driest places. Observation times vary by site and through history. Record for an observation day. A well maintained station furnishes an excellent climate record. Subset called Historical Climate Network meet standards for longevity, data completeness, number of station moves. Data quality and maintenance were not considered in selecting this network. Overall quality about like the rest. Fire Weather Cooperative Network Operator: Fire agencies Archive: US Forest Service Measurement interval: Daily Record length: Several decades Manual Max temp, min temp, precipitation, snowfall, snowdepth, sky state, humidity, wind Reporting interval: Daily, by 1 pm local time Purpose: Assessment of fuel and fire conditions Once daily readings usually at 1 pm. Number of stations has greatly reduced because of growth of RAWS network. Many were in interesting and unusual locations: ranger stations, fire lookouts, remote locations. Had humidity and wind. Very bad time for observations, but needed by 2 pm to calculate fire danger rating. Generally seasonal, warm season (fire season). Not much used any more but these did record for many years. RAWS Network Operator: multi-agency, primarily BLM and USFS, other federal and state Archive: Western Regional Climate Center Measurement interval: Hourly Record length: earliest about 1983, mostly 1985 onward Automated Temp (was 10-min just before reporting time), relative humidity, precipitation, wind (usually 20 ft), solar radiation (varies, instantaneous to hourly), fuel temperature, some have soil temperature. Reporting interval: Three hourly, or hourly. Purpose: Originally fire, now becoming more multi-purpose Approximately 1600-2000 sites meeting FPA (Fire Program Analysis) standards, approximately 2400 altogether. Maintained out of NIFC. Remote locations, unheated unshielded tipping bucket precip gages. Can get buried by snow. Some are turned off over winter but most keep functioning. One-way GOES transmission. Minimal quality control, thus far. This will probably be changing. Snotel network Operator: National Resources Conservation Service Archive: NRCS Water and Climate Center, Portland Measurement interval: 15 minutes Record length: late 1970s / early 1980s to present Automated Instantaneous temperature every 15 min, snow water equivalent, snow depth (recently), accumulated water year precipitation, soil temperature and soil moisture at some sites Reporting interval: Mostly hourly, some 3 or 6 hourly Purpose: Water supply evaluation and forecasting A rugged all weather system, designed for heavy snow and rain, resolution to 0.1 inch, remote and elevated locations, snow zone up to near or below timberline. Generally very good measurements. Site exposure history not always well documented, or else hard to access. Report via meteorburst, thus 2-way communication. June Lake Snotel. Sasquatch PAWS (Public Agricultural Weather System), Ag Weather Network Operator: WSU Center for Precision Agricultural Systems, Prosser Archive: WSU Center for Precision Agricultural Systems, Prosser Measurement interval: 15 minutes. Record length: 100+ years Automated Temp, precip, relative humidity, solar radiation, wind (about 2 m), soil moisture, soil temperature (multiple depths), leaf wetness Reporting interval: Hourly Purpose: Agricultural weather and climate Approximately 59 stations at present. Stations are in agricultural settings, often near vegetation, many climate heavily modified. Sensing at 10 sec intervals, averaged to 15 min, reported hourly. PAWS Standard Weather Station CR10X: CR10 datalogger w/CR10WP and 64K RAM ENC 12/14: Enclosure w/mounts (12"x 14") MSX10R: Solar Panel w/regulator HMP35C-L10: Vaisala temp and RH probe w/10 ft lead 41002-2: 12 plate gill radiation shield LI200S: LI-COR silicon pyranometer LI2003S: LI-COR Py. Base and leveling fixture 03001-5: Wind set RM Young TE525: Tex. Elec. Rain Gauge (0.01"/TIP) 227: Soil moisture block 237: Wetness sensing grid 105T: CU-Const thermocouple w/10 ft lead 10TCRT: Thermistor reference for CR10 P50UHF: 5 watt UHF transceiver RF95: RF modem Tripod: cross-arm, mounting arm and grnd kit 019ALU: Aluminum Crossarm Sensor mnt 025: Pyranometer crossarm stand. Battery enclosure 10 ft antenna cable w/connectors UHF Yagi antenna 70 AHR battery Padlocks Leaf wetness mounting bracket Agrimet network Operator: Bureau of Reclamation Archive: Bureau of Reclamation Measurement interval: 15 minutes Record length: 1983 (earliest) and late Automated Temp, precip, wind (2 m), relative humidity, solar radiation, soil temperature, leaf wetness, pressure, evaporation at some. Reporting interval: Hourly Purpose: Agriculture and especially water use and irrigation Approximately 70 sites, mostly in Columbia Basin and Pacific Northwest. Mostly in agricultural settings. Well maintained, well managed system, with good quality control. ASOS Automated Surface Observing System Operator: National Weather Service, some are
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