Data for: Stable isotope-inferred hydrology of ponds created by the Mount St. Helens eruption

Freshwater ponds are prevalent globally and provide critical ecosystem functions (e.g., water storage and groundwater recharge), yet little is known of their hydrological features immediately following formation.  We analysed stable isotopes of water (δ2H, δ18O) to characterize spatio-temporal hydrologic variation in ponds created by the Mount St. Helens eruption.  We also examined how climate and landscape features interact to regulate local hydrology.  Ponds were sampled for isotopic analysis in spring (2015, 2017, 2018) and summer (2018).  Mass balance models characterized the water balance of ponds (evaporation: inflow; E:I), as well as water sources (rain, snow).  Other variables were measured in situ (temperature, conductance), collected from data sources (meteorology), or quantified with remote sensing (vegetation).  Bayesian estimates of standard ellipse areas (SEAB) were used to compare isotopic values among years, whereas linear models were used t..., There are two datasets included: 1) environmental data; and 2) isotope data. 
Variables in the environmental dataset were collected several ways, including in situ measurements (water temperature, specific conductance), analyzed in a laboratory following sampling (dissolved organic carbon), compiled from outside data sources (meteorological variables), or quantified with remote sensing (normalized difference vegetation index).  Data processing is described in the manuscript.
Variables in the isotope dataset were analyzed in a laboratory following sampling (δ2H and δ18O), compiled from outside data sources (meteorological variables), or represent intermediate calculations.  Briefly, water samples were collected by immersing high-density polyethylene bottles, which were then sealed tightly to prevent water evaporation.  Samples were filtered through glass fiber filters (VWR, 0.45-µm pore size) on the day of collection, and the filtrate frozen until for further chemical..., , # Data for: Stable isotope-inferred hydrology of ponds created by the Mount St. Helens eruption

[https://doi.org/10.5061/dryad.0zpc8675s](https://doi.org/10.5061/dryad.0zpc8675s)

Datasets consist of environmental data and isotope data.

## Description of the data and file structure

Missing data indicated with NA.

**environmental_data_final.csv**

uniqueID – a unique sample identifier to join environmental dataset with isotopic dataset     

date – sample date; MM/DD/YYYY

year - sample year        

pond – name of pond (M: Maratta region; H: Hummocks region)           

region – Hummocks or Maratta              

elev_m - elevation of ponds, derived from GPS measurements taken from pond shore; meters

lat – latitude of ponds, from GPS coordinates taken from pond shore; decimal degree              

long – latitude of ponds, from GPS coordinates taken from pond shore; decimal degree                          

hydroperiod – categorical classification of pond hydroperiod 

depth_cm – m...,