Modeled trends in phenological advancement and sensitivity for three northeastern alpine species are less pronounced compared with lower elevations in the region, and this small shift in flower timing did not increase risk of frost damage. Potential reasons for limited earlier phenological advancement at higher elevations include a slower warming trend and increased cloud exposure with elevation and/or inadequate chilling requirements.

The focus of this article is both a region and a type of cave not typically associated with ice caves. Nevertheless, both the region and the type play an important role in American ice-cave research. Talus-and-gorge ice caves in the northeastern United States can be used as climate indicators for a whole region; and therefore, they are the target of this young field of research. Ice caves, in general, are sensitive climatopes that can serve as excellent indicators for short and long term changes in the climate of a region, principally because of shifts between phases of increasing ice growth and melting during a year and over time. This research started with an investigation of known talus-and-gorge ice caves, followed by environmental monitoring of selected caves with perennial ice that were equipped with temperature sensors recorded over four years. This is one of the world's longest high-resolution climatologic monitoring record of such caves. In addition, the height of the ice was surveyed annually at a time when ice would most likely be at its minimum, the start of November. This allowed for investigation of the annual changes and the influence of the temperature over the previous year. Some predictions for the future of the ice caves and the whole region could be deduced from the data. At the moment, there is no sign of either a renewed increase in the number of talus-and-gorge ice caves or an increase in ice accumulation within the existing ones.D. Holmgren, A. Pflitsch, K. Rancourt, and J. Ringeis. Talus-and-gorge ice caves in the northeastern United States past to present-A microclimatological study.

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A field campaign featuring three collocated Doppler wind lidars was conducted over ten days during September 2000 at the GroundWinds Observatory in New Hampshire. The lidars were dissimilar in wavelength and Doppler detection method. The GroundWinds lidar operated at 532 nm and used fringe-imaging direct detection, while the Goddard Lidar Observatory for Winds (GLOW) ran at 355 nm and employed double-edge filter direct detection, and the NOAA mini-MOPA operated at 10 microns and used heterodyne detection. The objectives of the campaign were (1) to demonstrate the capability of the GroundWinds lidar to measure winds while employing several novel components, and (2) to compare directly the radial wind velocities measured by the three lidars for as wide a variety of conditions as possible. Baseline wind profiles and ancillary meteorological data (temperature and humidity profiles) were obtained by launching GPS radiosondes from the observatory as frequently as every 90 minutes. During the final week of the campaign the lidars collected data along common lines-of-sight for several extended periods. The wind speed varied from light to jet stream values, and sky conditions ranged from clear to thick clouds. Intercomparisons of overlapping lidar and radiosonde observations show that all three lidars were able to measure wind given sufficient backscatter. At ranged volumes containing thick clouds, and those beyond, the wind sensing capability of the direct detection lidars was adversely affected.

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