Gridded CLIGEN Processing

GEE code that calculates CLIGEN input parameters from global climate products

The scripts in this repository ARS-SWRC/Gridded-CLIGEN-Processing are used to calculate CLIGEN input parameters directly from global climate datasets. Bias adjustments for the resulting parameter values are not currently part of this code. The scripts only require a GEE asset representing point geometries. To create this asset, make_grid_point_asset.py may be used to get grid points at the resolution of selected climate products for clipped regions.

Goals

• Create Google Earth Engine code to calculate CLIGEN input parameters.
• Test possibilities for optimizing the code to reduce run-time.
• Run the code for large regions.

GEE Point Geometry Assets

Description	Path	n	Resolution
Northern Latitude Band Grid	("users/andrewfullhart/Northern_ERA_Grid")	114951	0.25 arc deg
Southern Latitude Band Grid	("users/andrewfullhart/Southern_ERA_Grid")	37105	0.25 arc deg

Monthly CLIGEN Input Parameters

Parameter	Label	Script	Climate Product	Band
Mean of daily precip. for "wet" days in the month	MEAN P	precip_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	total_precipitation
Standard deviation of daily precip. for "wet" days in the month	S DEV P	precip_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	total_precipitation
Skewness of daily precip. for "wet" days in the month	SKEW P	precip_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	total_precipitation
Transition probability of a wet day given a wet day	P(W/W)	precip_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	total_precipitation
Transition probability of a wet day given a dry day	P(W/D)	precip_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	total_precipitation
Maximum 30-min intensity in month averaged by years	MX.5P	intensity_subdaily_variable.py	GPM ("NASA/GPM_L3/IMERG_V06")	precipitationCal
Time-to-peak-intensity cumulative probability dist.	TimePk	-	-	-
Mean of maximum daily temperature	TMAX AV	temp_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	maximum_2m_air_temperature
Mean of minimum daily temperature	TMIN AV	temp_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	minimum_2m_air_temperature
Standard deviation of maximum daily temperature	SD TMAX	temp_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	maximum_2m_air_temperature
Standard deviation of minimum daily temperature	SD TMIN	temp_daily_variables.py	ERA5 ("ECMWF/ERA5/DAILY")	minimum_2m_air_temperature
Mean of Daily Incoming Solar Radiation	SOL.RAD	solrad_daily_variables.py	GLDAS ("NASA/GLDAS/V021/NOAH/G025/T3H")	SWdown_f_tavg
Standard Deviation of Daily Incoming Solar Radiation	SD SOL	solrad_daily_variables.py	GLDAS ("NASA/GLDAS/V021/NOAH/G025/T3H")	SWdown_f_tavg
Various Wind Parameters	-	-	-	-