Meteorology - Humidity
This page contains detailed information for the meteorology humidity component.
On this page:
Description
Humidity is the measure of water vapor present in the air. Humidity directly affects evaporation in hydrologic cycle. There are several measures of humidity. Relative humidity and dew point temperature are the two most commonly used measures. Relative humidity at a given air temperature is the amount of water vapor in air expressed as percentage of the amount needed to achieve saturation at the same temperature. The dew point is the temperature the air needs to be cooled to in order to achieve saturation while maintaining constant pressure. If the air were to be cooled further, water vapor would have to come out of the atmosphere in the liquid form, usually as fog or precipitation.
Input Parameters
Attributes of the HMS humidity input object
Output Data Format Options
| Parameter | DataType | Description | Comments |
|---|---|---|---|
| Source | Drop-down list | Time-series data source | Valid sources: prism |
| Parameter | Drop-down list | Parameter to specify the humidity dataset | Available parameters: relative humidity, dew point |
| Start Date | String | Start date for the output timeseries. e.g., 01/01/2010 | Data Availability prism: daily 1/1/1981-Present (~6-month lag); Conterminous U.S. @ 4-km resolution. |
| End Date | String | End date for the output timeseries. e.g., 01/01/2010 | |
| Location Option | Drop-down list | Location of interest options. | Valid options: Latitude/Longitude, Catchment Centroid. Output time-series is returned for the latitude/longitude at the centroid of the NHDPlusV2.1 catchment when 'catchment (COMID)' is selected. |
| Latitude | Number | Latitude coordinate for the output timeseries. e.g., 33.925575 | Used only when 'Latitude/Longitude' is selected for 'Location Option'. |
| Longitude | Number | Longitude coordinate for the output timeseries. e.g., -83.356893 | Used only when 'Latitude/Longitude' is selected for 'Location Option'. |
| Catchment COMID | String | NHDPlusV2.1 catchment COMID. | Used only when 'catchment Centroid' is selected for 'Location Option'. |
| Local Time | Drop-down list | Time zone for the timestamp in output time-series. | Valid options: GMT |
| Temporal Resolution | Drop-down list | Temporal resolution/timestep of the output time-series. | Valid options: daily, monthly. |
| Output Date Format | String | Format of the returned numeric values. | Valid options: E E0, E1, E2, E3, e, e0, e1, e2, e3, F, F0, F1, F2, F3, G, G0, G1, G2, G3, N, N0, N1, N2, N3, R. Details are available in the table below. |
Output Data Format Options
| Format Specifier | Name | Example |
|---|---|---|
| "E" or "e" | Exponential (Scientific).Exponential notation. | "E": 1052.0329112756 -> 1.052033E+003"e": 1052.0329112756 -> 1.052033e+003"E2": -1052.0329112756 -> -1.05E+003"e2": -1052.0329112756 -> -1.05e+003 |
| "F" | Fixed-point.Integral and decimal digits with optional negative sign. | "F": 1234.567 -> 1234.57"F1": 1234 -> 1234.0"F4": -1234.56 -> -1234.5600 |
| "G" | General.The more compact of either fixed-point or scientific notation. | "G": -123.456 -> -123.456"G4": 123.4546 -> 123.5"G": -1.234567890e-25 -> -1.23456789E-25 |
| "N" | Number.Integral and decimal digits, group separators, and a decimal separator with optional negative sign. | "N": 1234.567 -> 1, 234.57"N1": 1234 -> 1, 234.0"N3": -1234.56 -> -1, 234.560 |
| "R" | Round-trip.A string that can round-trip to an identical number. | "R": 123456789.12345678 -> 123456789.12345678"R": -1234567890.12345678 -> -1234567890.1234567 |
Output Parameters
Attributes of the HMS humidity output object
| Column | DataType | Description |
|---|---|---|
| dataset | String | Primary dataset of the requested timeseries. Some API calls return more than one dataset, either for a workflow API or other relevent dataset. |
| dataSource | String | Primary source of the requested timeseries. |
| metaData | Dictionary | Metadata for the output timeseries, includes metadata from the source as well as HMS metadata. |
| data | Dictionary | Output timeseries data is returned as a dictionary, where the key is the datetime stamp and value is a list of values for the source/dataset. |
Web Service Details
Swagger UI
HTTP API
| Method | URL |
|---|---|
| POST | https://qed.epa.gov/hms/rest/api/v3/meteorology/humidity/ |
Change Log
Version: 0.1 Beta : May 29, 2019
- Production UI and documentation initial setup.