EARS-NWC near real-time reference validation

Near real-time validation of the PPS products (cloudmask, cloudtype and ctth) from the EARS-NWC service is being performed against the SMHI reference station output (direct readout in Norrköping) and displayed here.

Near-real time plots and statistics

Description of plots

The real-time plots displayed above show the EARS-NWC consistency with Direct Readout data from the Norrköping station. Here is a brief explanation to some of those plots.

CTTH scatter plot

Metop-B_201510220944_201510220959_ctth_scatter.png (92979 kb)

The scatter plot shows the Cloud Top Temperature of the CTTH product for the concatenated EARS-NWC scene against the corresponding parameter from the direct reception at Norrköping, and processed at SMHI. The comparison is only done on pixels where both products have valid data. The deviations in cloud top temperature may be due to differences in geolocation accuracy and different NWP input (both with respect to the actual NWP model used and the forecast lead time). At SMHI we use the full model state from ECMWF, whereas in the EARS-NWC processing uses input from the ECMWF model thinned in the vertical from 137 levels to 91.

Cloudtype confusion histogram

Metop-B_201510220944_201510220959_cloudtype_mixed_histogram.png (76186 kb)

The histogram like the one above tries to illustrate how the two cloud type products agree and disagree. If one disregards the different colors the histogram shows the distribution of cloudtype pixels according to the EARS-NWC produtc. The different colors shows the pixel values in the corresponding SMHI product. So for example in the case above some of the fractional clouds in the SMHI product becomes very low and low clouds (and a few thin cirrus) in the EARS-NWC cloudtype product.