International;
Center;
for;
Climate;
and;
Environment;
Sciences,;
Institute;
of;
Atmospheric;
Physics,;
Chinese;
Academy;
of;
Sciences,;
Beijing;
100029,;
China;
International;
Center;
for;
Climate;
and;
Environment;
Sciences,;
Institute;
of;
Atmospheric;
Physics,;
Chinese;
Academy;
of;
Sciences,;
Beijing;
100029,;
China;
3DVAR,; linear; balance; constraint,; nonlinear; balance; constraint,; background; error; covariance; matrix,; sea; surface; dynamic; height.;