Hydrological and temperature variations between 1900 and 2016 in the Catskill Mountains, New York, USA

Abstract

The Catskill Mountains and surrounding counties in south‐central New York State are home to almost 400,000 residents, and supply drinking water to over 9 million people in New York City and other municipalities. In this study, we identify a set of stations in this region that are appropriate for climatological analysis, and examine variations in precipitation, streamflow, and temperature between 1900 and 2016, extending the time domain of previous studies of the climatology of this region during both the early and recent portions of the record. Temperatures have increased since the mid‐20th century, in particular daily minimum temperatures, at rates that vary with season and elevation. As a result, diurnal temperature ranges have tended to decrease, particularly during the warm season at lower elevations. The most significant hydrological events include the cold drought of the 1960s (a year‐round phenomenon), and the wet period beginning in the late 1990s (primarily a warm season phenomenon). We also find evidence of a particularly wet period at the start of the 20th century. Cyclic behaviour is found in both hydrological and temperature records, with the most prominent cycle in cold season precipitation and streamflow peaking at 28 years.