| 7 | | > ds <- "http://www.meteo.unican.es/tds5/dodsC/system4/System4_Seasonal_15Members.ncml"; |
| 8 | | > openDAP.query <- loadSystem4(dataset = ds, var = "tasmin", members = 1, |
| 9 | | + lonLim = c(0,30), latLim = c(35,65), |
| 10 | | + season = 1, years = 1981:2000, leadMonth = 1) |
| | 7 | > loadSystem4(dataset, var, members, lonLim, latLim, season, years, leadMonth) |
| 15 | | * `dataset`: A character string indicating the full URL path to the OPeNDAP dataset. Currently, the accepted values correspond to the System4 datasets described in Section [https://www.meteo.unican.es/trac/meteo/wiki/SpecsEuporias/DataServer/Datasets Datasets], as specified in the above example, but using the `System4_Seasonal_15Members.ncml`, `System4_Seasonal_51Members.ncml` or `System4_Annual_15Members.ncml` ending strings. |
| 16 | | * `var`: Variable code. Argument values currently accepted are `tas`, `tasmin`, `tasmax`, `pr` or `mslp`, as internally defined in the dictionary defined for System4 following the nomenclature displayed in the table below. However, note that new variables and datasets will be progressively included. Note that System4 precipitation is internally deaccumulated by the function to return daily accumulated values. |
| | 12 | * `dataset`: A character string indicating the full URL path to the OPeNDAP dataset. Currently, the accepted values correspond to the System4 datasets described in Section [https://www.meteo.unican.es/trac/meteo/wiki/SpecsEuporias/DataServer/Datasets Datasets], for instance `http://www.meteo.unican.es/tds5/dodsC/system4/System4_Seasonal_15Members.ncml`, but using the `System4_Seasonal_15Members.ncml`, `System4_Seasonal_51Members.ncml` or `System4_Annual_15Members.ncml` ending strings depending on the dataset of choice. |
| | 13 | * `var`: Variable code. Argument values currently accepted are `tas`, `tasmin`, `tasmax`, `pr` or `mslp`, as internally defined in the vocabulary for System4 following the nomenclature displayed in the table below. However, note that new variables and datasets will be progressively included. Note that depending on the time step of the variable the units might be referred to different time aggregations. For instance, currently `mslp` is 6-hourly, and thus the 6-hourly mean value is returned for each time step. Similarly, 24-h accumulated values are returned for `pr`, and so on. Note that the ''instantaneous'' and ''aggregated'' fields in table below refer to the potential time step values that the variables may take, which does not mean that the resolution provided by the System4 model is necessarily that. |
| 18 | | ||='''Short Name'''=||='''Dataset variable'''=|| |
| 19 | | ||tasmax ||Maximum temperature at 2 metres since last 24 hours surface || |
| 20 | | ||tasmin ||Minimum temperature at 2 metres since last 24 hours surface || |
| 21 | | ||tas ||Mean temperature at 2 metres since last 24 hours surface || |
| 22 | | ||pr ||Total precipitation surface || |
| 23 | | ||mslp ||Mean sea level pressure surface || |
| | 15 | ||='''Short Name'''=||='''Long name'''=||='''Units'''=||='''Instantaneous'''=||='''Aggregated'''=|| |
| | 16 | ||tasmax ||Maximum temperature at 2 metres ||degC||No||Yes|| |
| | 17 | ||tasmin ||Minimum temperature at 2 metres ||degC||No||Yes|| |
| | 18 | ||tas ||Mean temperature at 2 metres ||degC||Yes||Yes|| |
| | 19 | ||pr ||Total precipitation accumulated||mm||No||Yes|| |
| | 20 | ||mslp ||Mean sea level pressure ||Pa||Yes||Yes|| |
| 28 | 25 | * `season`: A vector of integers specifying the desired season (in months, January=1, etc.) of analysis. Options include a single month (as in the above example) or a standard season (e.g. `period = c(12,1,2)` for standard Boreal winter, DJF). |
| 29 | 26 | * `years`: Optional. Default to all available years. Vector of years to select. Note that in cases with year-crossing seasons (e.g. winter DJF, `season = c(12,1,2)`, for a particular year period `years = 1981:2000`), by convention the first season would be DJF 1980/81, if available (otherwise a warning message is given). |
| 33 | | The output of the function is a data structure with all the requested information as follows. |
| | 31 | * `VarName`: Character string indicating the variable long name, as defined in the vocabulary (see Table above) |
| | 32 | * `VarUnits`: Character string. Units of the variable, as returned in `MemberData` |
| | 33 | * `TimeStep`: A `difftime` class object. Indicates the time span of each forecast time |
| | 34 | * `MemberData`: This is a list of length ''n'', where ''n'' = number of members of the ensemble selected by the `member` argument. Each element of the dataset is a 2-D matrix of ''i'' rows `x` ''j'' columns, of ''i'' forecast times and ''j'' grid-points |
| | 35 | * `LatLonCoords`: A 2-D matrix of ''j'' rows (where ''j'' = number of grid points selected) and two columns corresponding to the latitude and longitude coordinates respectively. |
| | 36 | * `RunDates`: A `POSIXlt` time object corresponding to the initialization times selected. There is an initialization time associated to each forecast time. |
| | 37 | * `ForecastDates`: A list with two `POSIXlt` time elements of length ''i'', corresponding to the rows of each matrix in `MemberData`. The list contain tow elements: |
| | 38 | * `Start`: Starting times of the verification period of the variable |
| | 39 | * `End`: End time of the verification period of the variable |
| 35 | | {{{ |
| 36 | | > str(openDAP.query) |
| 37 | | List of 4 |
| 38 | | $ MemberData :List of 1 |
| 39 | | ..$ : num [1:930, 1:1600] 275 277 278 279 277 ... |
| 40 | | $ Coordinates : num [1:1600, 1:2] 64.5 63.7 63 62.2 61.5 ... |
| 41 | | ..- attr(*, "dimnames")=List of 2 |
| 42 | | .. ..$ : NULL |
| 43 | | .. ..$ : chr [1:2] "lat" "lon" |
| 44 | | $ RunDates : POSIXlt[1:30], format: "1981-12-01" "1982-12-01" "1983-12-01" ... |
| 45 | | $ ForecastDates: Date[1:930], format: "1982-01-01" "1982-01-02" "1982-01-03" ... |
| 46 | | }}} |
| 47 | | |
| 48 | | The output consists of a list with the following 4 elements: |
| 49 | | |
| 50 | | * `MemberData`: This is a list of length ''n'', where ''n'' = number of members of the ensemble selected by the `member` argument. Each element of the dataset is a 2-D matrix of ''i'' rows `x` ''j'' columns, of ''i'' forecast times and ''j'' grid-points |
| 51 | | * `Coordinates`: A 2-D matrix of ''j'' rows (where ''j'' = number of grid points selected) and two columns corresponding to the latitude and longitude coordinates respectively. |
| 52 | | * `RunDates`: A `POSIXlt` time object corresponding to the initialization times selected. |
| 53 | | * `ForecastDates`: A vector of class `Date` of length ''i'', corresponding to the rows of each matrix in `MemberData`, containing the verification dates. |
