NAME Weather::GHCN::Fetch - Access the NOAA GHCN Global Historical Climatology Network repository VERSION version v0.0.002 DESCRIPTION The Weather::GHCN module library provides classes that can be used to develop applications that access weather data collected by the U.S. National Oceanic and Atmospheric Administration. The modules enable the retrieval of the surface station weather data and metadata that NOAA publishes as the Global Historical Climatology Network (GHCN) data repository, which is fed by weather data sources from around the world. NOAA GHCN DATA SOURCES The main data sources are: * * * NOAA also provides a readme file here: * APPLICATION SCRIPTS The Weather::GHCN::Fetch package includes fully functional application scripts that are based on Weather::GHCN::App modules. These are: ghcn_fetch Fetches station and/or weather data for reporting. ghcn_extremes Reports temperature extremes, including heatwaves and coldwaves, from station-level daily weather retrieved by ghcn_fetch. ghcn_station_counts Take a list of stations found by ghcn_fetch, examines the active date range, and produces a count of stations that were active in each year of the range. The output from all scripts is tab-separated and designed for easy import into Excel (or similar) for analysis, reporting and charting. ghcn_extremes and ghcn_station_counts are designed to take the output from ghcn_fetch via pipeline. Each script has a -help option that documents its features and options. APPLICATION MODULES The application scripts are mostly just a thin veneer over corresponding modules in the Weather::GHCN::App namespace. That and the POD necessary for -help and -usage. The application scripts are built upon the API modules, primarily Weather::GHCN::StationTable. API MODULES The API modules are the heart of the package, encapsulating the logic necessary for accessing the GHCN repository, downloading station metadata and daily weather data, managing the plethora of options supported by the ghcn_fetch application, etc. The modules are: Weather::GHCN::StationTable Weather::GHCN::Station Weather::GHCN::Common Weather::GHCN::CountryCodes Weather::GHCN::Measures Weather::GHCN::Options Weather::GHCN::TimingStats This module, Weather::GHCN::Fetch, is actually just a stub that provides documentation and a primary module name for the distribution. EXAMPLES The primary usefulness of this package comes from the application scripts. Here are some examples: List the weather stations in NY state with "New York" in the name: "ghcn_fetch -country US -state NY -location "New York"" List the New York weather stations active between 1900 and 1920: "ghcn_fetch -cou US -st NY -location "New York" -active 1900-1920" Report the yearly max, min and average temperatures at JFK airport: "ghcn_fetch yearly -cou US -st NY -location "New York JFK"" Report the monthly max, min and average temperatures at JFK airport: "ghcn_fetch monthly -cou US -st NY -location "New York JFK"" Report the daily max, min and average temperatures at JFK airport: "ghcn_fetch daily -cou US -st NY -location "New York JFK"" Launch the GUI for an options dialog "ghcn_fetch -gui" (requires Tk and Tk::Getopt to be installed) Get documentation on all the options "ghcn_fetch -help" Find the 5-day heatwaves at the JFK airport station: "ghcn_fetch id -cou US -st NY -location "New York JFK" | ghcn_extremes" Find the 3-day coldwaves at the JFK airport station: "ghcn_fetch id -cou US -st NY -location "New York JFK" | ghcn_extremes -cold -ndays 3" For each year between 1900 and 1950, count the number of active weather stations in NY state: "ghcn_fetch id -cou US -st NY -active 1900-1950 | ghcn_station_counts" AUTHOR Gary Puckering (jgpuckering@rogers.com) LICENSE AND COPYRIGHT Copyright 2022, Gary Puckering