Synoptic climate evidence of a late-twentieth century change to earlier spring ice-out on Maine Lakes, USA

• Published in: Climatic change Vol. 153; no. 3; pp. 323 - 339
• Main Authors: Ellis, Andrew W., Greene, Timothy R.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2019; Springer Nature B.V
• Subjects: Air temperature; Atmospheric Sciences; Climate; Climate change; Climate Change/Climate Change Impacts; Climate teleconnections; Climatic data; Earth and Environmental Science; Earth Sciences; El Nino; El Nino phenomena; Ice; La Nina; Lake ice; Lakes; Pacific-North American (PNA) pattern; Precipitation; Spatial data; Spring; Trend analysis; Weather; Weather types; Winter; Winter precipitation; United States > US; Maine
• ISSN: 0165-0009; 1573-1480
• DOI: 10.1007/s10584-019-02398-6

Trend analysis of spring ice-out on eight lakes within the state of Maine of the northeastern USA reveals a change to earlier occurrence by 1 to 2 weeks over the period 1956–2015. Much of the trend occurred from the late 1970s through the 1980s, but a secondary trend toward earlier ice-out appears to have begun in the late 1990s. Synoptic climate data support local and hemispheric climate evidence of increasingly earlier ice-out, particularly during the earlier period of pronounced change. Local spring and winter maximum daily air temperatures increased while winter precipitation decreased; synoptic weather types of moderate temperature character increased in frequency, while polar types became less frequent; synoptic weather types became warmer in spring and winter, and in spring, warmer weather types became wetter, while cooler weather types became drier; and two key climate teleconnections, the Pacific-North American pattern and the El Niño/La Niña pattern, changed significantly toward a phase historically associated with earlier ice-out. While the results underscore the value in monitoring and study of lake ice as a climate proxy, they also demonstrate the value of synoptic climate data for filling the spatial gap between local and large-scale climate data in studies of lake ice phenology.