More than half of the overall Eta domain (top set of results) is over the
oceans. What are the main differences between the mixture of observations
most affecting temperatures in the analysis over the oceans and the mixture
of observations most affecting temperatures in the analysis over the CONUS
in this case? Choose all choices that apply, then click Done. (To undo a selection,
click the choice again.)
Discussion
Over the CONUS, the RAOB mass and wind data and ACARS mass and wind data
stand out as having by far the greatest impact on analysis temperatures, with
surface mass data also impacting analysis temperatures at 850 hPa. Over the
whole Eta domain, and thus over the oceans, a much broader array of data types
contributed more to the analysis (choice e), with satellite data especially
having more impact than over the CONUS (choice d).
Counterintuitively, RAOB data had as large an impact over the whole domain
as over the CONUS for two reasons. The broad range of data influence (forecast
error covariance functions) allowed data from coastal stations to affect the
analysis over the adjacent ocean areas. And, the 12-hour cycling of data and
short-range forecasts allowed information from over land to advect for 12
hours over the oceans.
Surface data (includes marine and land observations) were a little more
influential over oceans perhaps because there was less other data providing
similar information. ACARS data were more influential over the CONUS because
that's where most of the flights of outfitted aircraft took place. The increased
impact of AIREP/PIREP data on the analysis outside the CONUS partly compensated
for this.