This is the README doc for the repository Scripts for Effects of Shifting Snowmelt Regimes on the Hydrology of Non-Alpine Temperate Landscapes. 
The including scripts were written in the code software R. They download, analyze and visualize hydrologic data used in the manuscript. 
A brief description of the scripts and how they relate is below.

Temperature Data:
The script HistoricalWeather.R downloads data from the Global Historical Climatology Network (GHCN) weather stations found in Michigan. 
It downloads daily minimum and maximum temperatures and saves them as a data frame. That data frame is then used in the script MITemperature.R. 
The temperature data is spatially aggregated across HUC-8 drainage basins and used in the multimetric analysis to classify winters as warm or cool. 

Snow Data:
The script SNODAS_Mean_SWE_BasinsAll.R downloads daily gridded files of SWE from the SNODAS FTP, spatially aggregates it across stream drainage basins and 
then merges those aggregates into one large data frame used for later analysis. The process of downloading and reading the SNODAS files references code in the 
snodas_helper_functions.R script. RegionalSWEAnalysis.R loads SNODAS SWE data aggregated across regional polygons (using shapefiles of the three state 
regions rather than the basin shapefiles used for aggregation in SNODAS_Mean_SWE_BasinsAll.R). It then calculates different annual and year type statistics 
for the regions and visualizes the results.

PRISM Data:
The scripts PRISMTempProcessing.R and PRISMMeanPrecipProcessing.R download daily gridded files of temperature and precipitation from the PRISM FTP, 
imports them into R, then extracts stream basin aggregates of these two variables for use in the groundwater analysis.

Stream Data:
The script USGS_Data.R downloads a list of USGS gage meta data, selects the gages in Michigan active for the desired time period and then downloads the 
daily discharge data for those gages. It then takes that daily discharge data and calculates various annual and year type statistics, as well as creating 
visualizations of results.

Groundwater Analysis:
The script Basin_GW_Final.R takes data frames of melt, precipitation and streamflow and uses them to calculate changes in net recharge (net storage) 
using a simple water budget equation. It then creates tables of statistics and figures of year type differences.