Evaluating and Extending the Ocean Wind Climate Data Record

Abstract

Satellite microwave sensors, both active scatterometers and passive radiometers, have been systematically measuring near-surface ocean winds for nearly 40 years, establishing an important legacy in studying and monitoring weather and climate variability. As an aid to such activities, the various wind datasets are being intercalibrated and merged into consistent climate data records (CDRs). The ocean wind CDRs (OW-CDRs) are evaluated by comparisons with ocean buoys and intercomparisons among the different satellite sensors and among the different data providers. Extending the OW-CDR into the future requires exploiting all available datasets, such as OSCAT-2 scheduled to launch in July 2016. Three planned methods of calibrating the OSCAT-2 measurements include 1) direct Ku-band intercalibration to QuikSCAT and RapidScat; 2) multisensor wind speed intercalibration; and 3) calibration to stable rainforest targets. Unfortunately, RapidScat failed in August 2016 and cannot be used to directly calibrate OSCAT-2. A particular future continuity concern is the absence of scheduled new or continuation radiometer missions capable of measuring wind speed. Specialized model assimilations provide 30-year long high temporal/spatial resolution wind vector grids that composite the satellite wind information from OW-CDRs of multiple satellites viewing the Earth at different local times.

An overview of offshore wind energy resources in Europe under present and future climate

“…Thus, wind speed is estimated as a function of the backscattered energy. More than a dozen satellites with microwave radiometers or scatterometers have become operational since 1987 . Table lists the main datasets derived from these instruments during the 21st century.…”

“…Table includes the products with the highest spatial resolution and the widest temporal coverage. However, it is important to take into account that commonly there are more products for each instrument than those listed in Table . All products are referenced to 10 m in height …”

“…More than a dozen satellites with microwave radiometers or scatterometers have become operational since 1987. 26,27 Table 1 lists the main datasets derived from these instruments during the 21st century. Databases that use scatterometers and the WindSat and soil moisture active passive datasets provide daily wind speed and wind direction, whereas the other databases contain only daily wind speed data.…”

“…However, it is important to take into account that commonly there are more products for each instrument than those listed in Table 1. 27 All products are referenced to 10 m in height. 28 The main advantage of the satellite wind data is that these datasets offer global coverage at daily temporal scale (two records per day).…”

Ultrahigh Resolution Scatterometer Winds near Hawaii

“…Unlike wind measurements from buoys, ships, and planes, scatterometers provide regular global wind vector estimates over large regions of open ocean. The large coverage and availability of scatterometer data proves useful for weather studies and prediction [1,5,6]. Traditional wind estimates are retrieved on a coarse 12.5 km or 25 km grid (referred to as L2B estimates) and are excellent for understanding large scale wind flow and other features.…”