CIMIS and Spatial CIMIS derived weather components.
This project summarizes weather data for water year 2015 and 2016 for the Bay Delta. The California 2015 water year goes from 2014-10-01 to 2015-09-30. The California 2016 water year goes from 2015-10-01 to 2016-09-30 (Note: 2016 was a leap year). There are a number of datasets available: daily and hourly weather for a subset of CIMIS stations; the CIMIS station data used for Spatial CIMIS; and Spatial CIMIS data clipped to the Delta.
Included in the project is a Makefile for recreating all these data. If you need a slightly different dataset, that should be helpful in processing steps. The Makefile uses httpie and jq for processing.
We have included data from the following CIMIS stations; arranged from North to South.
| Station | Station_id | Station | Station_id | |
|---|---|---|---|---|
| Esparto | 196 | Twitchell Island | 140 | |
| Fair Oaks | 131 | Concord | 170 | |
| Bryte | 155 | Brentwood | 47 | |
| Davis | 6 | Manteca | 70 | |
| Winters | 139 | Tracy | 167 | |
| Dixon | 121 | Pleasanton | 191 | |
| Lodi West* | 166 | Modesto | 71 |
*Lodi West (station ID = 166) went offline on 3/20/2015
You can use this handy Overview Map to locate where these stations are located.
The easiest way to download CIMIS station data is via the CIMIS API. In order to use that, you need to register to obtain an API key. Once registered, creating new station data is fairly straight forward. We simply used this API to download the data.
We then used jq to do a very simple process of the json data to a CSV file. If you need another format for this infomation, consider working directly with the JSON data, as it has more complete information then the csv files. See the Makefile for complete information, make csv.daily.
There is one file per station per water year.
Similar to the daily_station data, only using calls for hourly data from the CIMIS API. Made with make csv.hourly. There is one file per station per water year.
The data provided here is basically the same as can be found in the Spatial CIMIS download site but has been organized and reformatted. Users can go back to the original site for more infomation. Again, the Makefile provides useful clues for using this data.
Spatial CIMIS provides the following parameters:
| parm | unit | description |
|---|---|---|
| ETo | mm / d | ASCE Evapotranspiration |
| K | Clear Sky Factor | |
| Rnl | MJ/ m^2 d | Net Long Wave Radiation |
| Rso | MJ/ m^2 d | Calculated Clear Sky Radiation |
| Rs | MJ/ m^2 d | Net Short Wave Radiation |
| Tdew | C | Dew Point Temperature |
| Tn | C | Minimum Daily Temperature |
| Tx | C | Maximum Daily Temperature |
| U2 | m/s | Average Daily Wind Speed at 2m |
It is possible that the station data used at the time of the Spatial CIMIS calculations do not match the data currently provided. The station data used in the calculating the Spatial CIMIS rasters is included in the cimis/[water year]/ directory. We include the station data for each of the above Delta stations. We also include all the data used for every day. This data comes from the station.csv located in each directory from the Spatial CIMIS download site. Made with make csv.cimis.
Note the the headers for the cimis data and the station data are slightly different, but the correspondence between them is clear.
For each day, we have downloaded, clipped, and reformatted the Spatial CIMIS rasters as GeoTiff files. The arrangement is similar to as used in the Spatial CIMIS site. We use gdal_translate, in a manner similar to gdal_translate -a_srs EPSG:3310 -projwin -164000 68000 -108000 -44000 cimis/YYYY/MM/DD/ETo.asc cimis/YYYY/MM/DD/ETo.tif. Made with make cimis.daily.
For each month we combine each parameter into a multi-band tif image, one band for each day. This is to simplify input into image processing packages, potentially. Made with make cimis.monthly.
For each water year, we combine the months, starting from October to create a 365 band image of each parameter for each day. Again this is potentially useful for image processing.
Additionally, these data are uploaded into Google Earth Engine, in the shared area for the ssj-delta-cu project. Please contact us for information on access to that data.