A statewide grid surface (80m spatial resolution) delineating Chill Hours (CHR) accumulation across the state of Tasmania is produced daily for the Tasmanian winter season. Chill Hours is calculated as the number of hours where air temperature is between 0-7C for the period: 1 May to 31 August. The outputs are dynamic with the map products updated daily. Three map products are produced: 1) Chill Hours Accumulation Tracker - Current Season: CHR accumulation to date (refer to link below) for the current growing season (updated daily) 2) Chill Hours Accumulation Tracker - 10yr Average: CHR accumulation to date (refer to link below) based on the 10 year average (i.e. averaged CHR units garnered from data 10 years prior to the current growing season; updated daily) 3) Chill Hours Anomaly - Current Season vs 10yr Average: The difference between 1) and 2) where positive values indicate that the current growing season is cooler relative to the 10 year average, negative values indicate a warmer season. Map outputs are based on daily records produced from 43 Bureau of Meteorology (BoM) Automatic Weather Station sites with further bias correction provided by 267 independent air temperature logger recording sites (courtesy of the Tasmanian Government Department of Natural Resources and Environment (NRE)). For operational real-time application, the mapping was fully automated in the R programming language and hosted on a cloud-based computing platform courtesy of the high performance computing cluster provided by the Tasmanian Partnership of Advanced Computing (TPAC) of the University of Tasmania. Refer to the following link for details of the latest map updates: https://sdi.tas-hires-weather.cloud.edu.au/shiny/

The CHR maps are based on methods as adopted by the 'REAL-TIME AIR TEMPERATURE MAP OF TASMANIA' mapping system, refer here: https://www.thelist.tas.gov.au/app/content/data/geo-meta-data-record?detailRecordUID=ca55463d-f416-40e4-821f-92df3931313c Cross validation analysis of this system revealed that that on average, predictions are approximately within 1oC of the true temperature. It should be cautioned, however, that on rare occasions it was found that predictions can be erroneous by as much as 5oC from the true temperature. As such, the map products produced from this system should be treated as indicative of the true temperature and therefore the CHR maps should be treated similarly. The following web map service (wms) can be used to import live updates into a GIS: Current Season: https://sdi.tas-hires-weather.cloud.edu.au/geoserver/CHR_current/wms 10 year average: https://sdi.tas-hires-weather.cloud.edu.au/geoserver/CHR_historic/wms Current season vs 10 year average anomaly: https://sdi.tas-hires-weather.cloud.edu.au/geoserver/CHR_deviation/wms