Buoy wind inhomogeneities related to averaging method and anemometer type: application to long time series

摘要: Moored buoy observations began two to three decades ago. These datasets have value for calibration of remotely sensed data, validation weather and ocean wave models, input reanalysis studies climate trend variability. Changes in wind observation methods the potential introduce inhomogeneities into time series. include changes anemometer height (typically between 5 10 m) with platform type; transition 1980s 1990s from use a vector-mean scalar-mean averaging method; and, recent years, introduction ultrasonic anemometers networks, as well continued mechanical propeller-vane type anemometers. This study examines differences measurements RM Young Vaisala installed on same buoy, vector-averaged scalar-averaged speeds anemometer. also considers effect waves these differences. The comparisons are based large multi-year 6-m buoys boat-shaped hulls (6N) 3-m round (3D), deployed off coasts Canada northeast Pacific northwest Atlantic Oceans. Results comparison suggest that winds 0.16 ms−1 + 1.6% winds. vector scalar Canadian data show mean were 2.1% 2.7% greater than 6N 3D buoys, respectively. Vector-scalar increased increasing height, more quickly buoys. used adjust long-term Pacific. adjustment is shown be important or sustained speed, terms impact monthly speeds. A homogeneity testing program finds other unexplained significant shifts series Copyright © 2011 Royal Meteorological Society Crown right Canada.