5cm could be an over-estimate
MSL from reliable and geographically stable locations is closer to 1.5cm for 11years (+/-0.2) to start of 2019 (trend of 1.36mm/yr). Fort Denison (Sydney, Australia) is barely moving compared to places built on sinking mud/sand (like Jakarta which has huge buildings on soft ground which they pumped the water from under their feet so it sinks more). Did they tell you they calibrated the satellite results by adjusting sensor output by upto 75cm (early in orbit) and data is readjusted for drifting times&locations. How can they say these Jason satellites are more accurate than other sources to measure mm changes. Some physical data from Pacific Islands are garbage because sensors have lost backup battery capacity and only work during hours of sufficient sunlight. A NZ study found Pacific Islands were on average, not shrinking https://www.nature.com/articles/s41467-018-02954-1.
Antarctic sea ice coverage returned to 1979 level in the last few weeks.