Readme file for: SnowClim: Pre-industrial Climate Data
(https://www.hydroshare.org/resource/0c852b12f668438fb9f0188a1cc6e8a9/)


This .txt file was generated on 4 Nov 2021 by A.C. Lute.


Summary:
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This directory contains climate metrics for the pre-industrial period
and represents a subset of the SnowClim Dataset
(https://www.hydroshare.org/resource/acc4f39ad6924a78811750043d59e5d0/).
The SnowClim Dataset was developed following the methods presented in
Lute et al., (in prep). The pre-industrial climate data was created by
downscaling 4 km climate forcings from the Weather Research and
Forecasting (WRF) model (Rasmussen and Liu, 2017) over a thirteen year
period (1 Oct 2000 to 30 Sep 2013) and then perturbing the downscaled
data using multi-model mean deltas from CMIP5 to create climate data
that reflects conditions during 1850-1879. Climate data was summarized
into climate metrics at ~210 m spatial resolution for the western US.
Additional details about the downscaling approach can be found in Lute
et al., (in prep).


File Organization:
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Climate metrics are available in separate files. For accessibility,
metrics are available in both GeoTiff and netCDF format. The suffix
'_PRE' indicates that the data represents conditions under
pre-industrial climate. Metrics with values for each month have values
for January through December.


Metrics:
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- downwelling shortwave

	units: W m-2

	Monthly mean downwelling shortwave radiation at the surface,
	downscaled from WRF (Rasmussen and Liu, 2017; which accounts for
	cloud cover) using the R insolvent package to correct for aspect,
	self-shading, and shading by adjacent terrain.

- minimum air temperature (tmin)

	units: °C

	Monthly mean of daily minimum 2m air temperatures, downscaled from 
	WRF (Rasmussen and Liu, 2017) using local lapse rates.

- maximum air temperature (tmax)

	units: °C

	Monthly mean of daily maximum 2m air temperatures, downscaled from 
	WRF (Rasmussen and Liu, 2017) using local lapse rates.

- mean air temperature (tmean)

	units: °C

	Monthly mean of daily mean 2m air temperatures, downscaled from WRF
	(Rasmussen and Liu, 2017) using local lapse rates.

- mean dew point temperature (tdmean)

	units: °C

	Monthly mean of daily mean 2m dewpoint temperatures, downscaled 
	from WRF (Rasmussen and Liu, 2017) using local lapse rates.

- precipitation (ppt)

	units: meters (m)

	Monthly total precipitation, downscaled from WRF (Rasmussen and 
	Liu, 2017) using local lapse rates and bias corrected using PRISM
	precipitation data (PRISM Climate Group, 2015).

- number of temperature sign changes (tschange)

	units: count

	Annual number of times that temperature (°C) changes sign. 
	Calculated from 4-hourly air temperatures downscaled from WRF 
	(Rasmussen and Liu, 2017) using local lapse rates.


Sharing and access information:
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1. Licenses/restrictions placed on the data: 
This resource is shared under the Creative Commons Attribution CC BY.

2. Links to publications that cite or use the data: 
none yet

3. Links to other publicly accessible locations of the data: 
none

4. Links/relationships to ancillary data sets: 
SnowClim Model and Dataset
(https://www.hydroshare.org/resource/acc4f39ad6924a78811750043d59e5d0/)
SnowClim Model Code
(https://www.hydroshare.org/resource/dc3a40e067bf416d82d87c664d2edcc7/)
SnowClim Pre-industrial Snow Data
(https://www.hydroshare.org/resource/fc621d75985c4695b6758ade312241c6/)
SnowClim Present Climate Data
(https://www.hydroshare.org/resource/7e3678f00ad74bfd881f91d6f6f81494/)
SnowClim Present Snow Data
(https://www.hydroshare.org/resource/2dbd6e849a754c0981b99ee7c09031eb/)
SnowClim Future Climate Data
(https://www.hydroshare.org/resource/36895c3a2c53409893f5ba02ee142767/)
SnowClim Future Snow Data
(https://www.hydroshare.org/resource/96cba44cd74843639f855d7c9e22024b/)

5. Was data derived from another source? 
yes. Climate data was downscaled from the dataset of Rasmussen and Liu,
2017.

6. To cite this data, please reference both of the following:

Lute, A., J. Abatzoglou, T. Link (2021). SnowClim Model and Dataset,
	HydroShare,
	http://www.hydroshare.org/resource/acc4f39ad6924a78811750043d59e5d0
Lute, A.C., John Abatzoglou, and Timothy Link (in prep), SnowClim:
	high-resolution snow model and 	data for the Western United States.
	In preparation for submission to Geoscientific Model Development.


Authors:
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A.C. Lute, University of Idaho 
John Abatzoglou, University of California, Merced 
Timothy Link, University of Idaho


Contact Information:
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Please contact A.C. Lute with questions, concerns, or comments. Current
contact information is available on the webpage this file was downloaded
from.


References:
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Lute, A.C., John Abatzoglou, and Timothy Link (in prep), SnowClim:
	high-resolution snow model and 	data for the Western United States.
	In preparation for submission to Geoscientific Model Development. 
PRISM Climate Group, Oregon State University, http://prism.oregonstate.edu,
	created 27 May 2015. 
Rasmussen, R., and C. Liu. 2017. High Resolution WRF Simulations of the 
	Current and Future Climate of North America. Research Data Archive at 
	the National Center for Atmospheric Research, Computational and 
	Information Systems Laboratory. https://doi.org/10.5065/D6V40SXP. 
	Accessed 24 Sep 2018.