In aemon-j/LakeEnsemblR: Run Ensemble of Lake Models

knitr::opts_chunk$set(
  collapse = TRUE,
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Introduction

A key part of developing LakeEnsemblR was to develop a standardised format for model input data. This involved standard variable naming which includes units.

DateTime formatting

This package uses international standard format for date and time (ISO 8601), which is YYYY-mm-dd HH:MM:SS. For example: 2020-04-03 09:00:00.

Time Zones

Currently this is not accounted for so the timezone used in input is the timezone of output data. It is on the list of things to do.

Hypsograph data

The data needs to be a comma separated values (.csv) file where 0m is the surface and all depths are reported as positive. Area needs to be in meters squared. The column names must be Depth_meter and Area_meterSquared

Example of data:

Depth_meter,Area_meterSquared
0,3931000
1,3688025
2,3445050
3,3336093.492
4,3225992.455
5,3133491.11
6,3029720
...

Temperature Profile data

The data needs to be a comma separated values (.csv) file where the datetime column is in the format YYYY-mm-dd HH:MM:SS. Depths are positive and relative to the water surface. Water temperature is in degrees Celsius. The column names must be datetime, Depth_meter and Water_Temperature_celsius

Example of data:

datetime,Depth_meter,Water_Temperature_celsius
2004-01-05 00:00:00,0.9,6.97
2004-01-05 00:00:00,2.5,6.71
2004-01-05 00:00:00,5,6.73
2004-01-05 00:00:00,8,6.76
...

Meteorological data

The data needs to be a comma separated values (.csv) file where the datetime column is in the format YYYY-mm-dd HH:MM:SS. See table 1 for the list of variables, units and column names.

| Description | Units | Column Name | Status | |----------------|----------------|----------------|-----------------------------------------------------| | Downwelling longwave radiation | W/m2 | Longwave_Radiation_Downwelling_wattPerMeterSquared | If not provided,it is calculated internally from air temperature, cloud cover and relative humidity/dewpoint temperature | | Downwelling shortwave radiation | W/m2 | Shortwave_Radiation_Downwelling_wattPerMeterSquared | Required | | Cloud cover | - | Cloud_Cover_decimalFraction | If not provided,it is calculated internally from air temperature, short-wave radiation, latitude, longitude, elevation and relative humidity/dewpoint temperature | | Air temperature | °C | Air_Temperature_celsius | Required | | Relative humidity | \% | Relative_Humidity_percent | If not provided,it is calculated internally from air temperature and dewpoint temperature | | Dewpoint temperature | °C | Dewpoint_Temperature_celsius | If not provided,it is calculated internally from air temperature and relative humidity | | Wind speed at 10m | m/s | Ten_Meter_Elevation_Wind_Speed_meterPerSecond | Either wind speed or u and v vectors is required | | Wind direction at 10m | °C | Ten_Meter_Elevation_Wind_Direction_degree | Not required, but if provided u and v vectors are calculated internally | | Wind u-vector at 10m | m/s | Ten_Meter_Uwind_vector_meterPerSecond | Either wind speed or u and v vectors is required | | Wind v-vector at 10m | m/s | Ten_Meter_Vwind_vector_meterPerSecond | Either wind speed or u and v vectors is required | | Precipitation | mm/hr or mm/day | Precipitation_millimeterPerHour or Precipitation_millimeterPerDay | Not strictly required but is important for mass budgets in some models | | Rainfall | mm/hr or mm/day | Rainfall_millimeterPerHour or Rainfall_millimeterPerDay | Required | | Snowfall | mm/hr or mm/day | Snowfall_millimeterPerHour or Snowfall_millimeterPerDay | If not provided,it is calculated internally from rain when air temperature \< 0 degC | | Sea level pressure | Pa | Sea_Level_Barometric_Pressure_pascal | Not required | | Surface level pressure | Pa | Surface_Level_Barometric_Pressure_pascal | Required | | Vapour pressure | mbar | Vapor_Pressure_milliBar | If not provided,it is calculated internally from air temperature and relative humidity/dewpoint temperature | : Table 1. Description of meteorological variables used within LakeEnsemblR with units and required column names.

Inflow data

The data needs to be a comma separated values (.csv) file where the datetime column is in the format YYYY-mm-dd HH:MM:SS. See table 2 for the list of variables, units and column names. Providing inflow data is optional.

| Description | Units | Column Name | Status | |----------------------------------|-------|-----------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Discharge volumetric flow rate | m3/s | Flow_metersCubedPerSecond | Required | | Water temperature | °C | Water_Temperature_celsius | Required |
| Salinity | PSU | Salinity_practicalSalinityUnits | Required |
: Table 2. Description of inflow variables used within LakeEnsemblR with units and required column names.

LakeEnsemblR YAML configuration file

There is an example yaml configuration provided in the example dataset in the package or you can download a copy from GitHub here.

You will need to update each of the required variables in the location block to reflect your own site.

location:
   name: Feeagh                                 # station name used in output [default=GOTM site]
   latitude: 53.9                               # latitude [degrees North; min=-90.0; max=90.0; default=0.0]
   longitude: -9.5                              # longitude [degrees East; min=-360.0; max=360.0; default=0.0]
   elevation: 15                                # elevation of lake surface above sea level [m]
   depth: 46.8                                  # maximum water depth [m; min=0.0; default=100.0]
   hypsograph: LakeEnsemblR_bathymetry_standard.csv                 # hypsograph [default=]
   init_depth: 46.8                             # initial height of lake surface relative to the bottom [m]

Then input the filepaths to the bathymetry, meteorlogical and water temperature profile observations file. For first time users we would recommend to set up a folder with just these three files plus the LakeEnsemblR yaml configuration file.

Now you should be ready to run LakeEnsemblR on your site.

aemon-j/LakeEnsemblR documentation built on April 11, 2025, 10:09 p.m.