Extratropical cyclones over the North Atlantic and North Pacific: Comparison of AMSR2 — Retrieved and Era-Interim sea surface wind fields for 2 year period

Characteristics of Extratropical cyclones (ECs) over the North Atlantic and North Pacific are analyzed on the basis of Era-Interim re-analysis data and the fields of geophysical parameters, retrieved from the Advanced Microwave Scanning Radiometer 2 (AMSR2) measurements from GCOM-W1 satellite for two year period. ECs are identified in the fields of sea surface wind and sea surface pressure from re-analysis data. For all identified ECs AMSR2 - derived sea surface wind speed (SWS) fields are analyzed and compared with the Era-Interim re-analysis SWS fields. SWS values are obtained from AMSR2 data with the recently developed algorithm, extensively validated for the range of high winds (> 15 m/s). Special attention is given to the analysis of the hurricane-force ECs and the comparison of re-analysis and satellite-derived EC parameters. The hurricane-force EC numbers for both regions are also compared with those reported in previous publications. EC spatial distribution over both considered areas is estimated. It was found that the Era-Interim re-analysis underestimates the number of the hurricane-force ECs as compared with the estimates based on the AMSR2 derived SWS.