Extreme High Swell Events on the Moroccan Atlantic Coast

4.0 Case Study 1 » 4.3 Step 2: Compare the Marine Model Analyses with the Observations » 4.3.5 Model Wind Speed and Ship Observations

Overlaying the ECMWF 10 m wind speed analysis with ship observations is another way of checking the accuracy of the model forecast. But be aware that ship observations can sometimes be wrong.

ECMWF 10 m Wind With Ship Observations for 6 Jan 2014 0000 UTC

Question 1 of 2

For this situation, how well do the ECMWF 10 m wind speed and ship and buoy observations correlate?

For this situation, we generally see a good correlation between observed and modeled wind direction and speed, especially near the coast. Note the circled 50kt wind speed observation, where the model predicted 30kt.

Please make a selection.

Question 2 of 2

ECMWF 10 m Wind With Ship Observations for 6 Jan 2014 0000 UTC with one ob circled for an exericse

The model 10 m wind results in the chart do not agree with the circled 50kt ship observation. How should it be handled?

The circled observation shows a west wind with a speed of 50kts while the surrounding observations show lower winds. This isolated observation differs from the model observation and does not seem consistent with the model wind field or other buoys and ship observations. Despite this, caution should be exercised before automatically discarding the observation. Rather, you should review the ship’s previous observations, examine its consistency with the MSLP gradient, and then decide whether to trust the data.

Please make a selection.