Summary of NWP equations (cont.)
The
analysis error covariance is given by
This
can also be written as
ÒThe analysis precision is
given by the sum of the background and observation precisionsÓ
ÒThe
analysis covariance is reduced from the background covariance
by a factor (I - scaled
optimal gain)Ó
ÒThe variational approach and the sequential approach are solving the same problem,
with the same K, but only KF (or EnKF) provide an estimate of the analysis error covarianceÓ