Present contributions to sea level rise by thermal expansion and ice melting and implication on coastal management

• Results of climate models are in striking contrast with measurements.
• Since 2004 deep ocean water salinities and temperatures have changed minimally.
• Since 2000 sea ice extent has increased and surface air temperatures reduced.
• Since 2000sea levels have not risen for thermal expansion or melting of ice.
• Coastal management should follow experimentally driven pattern recognition and forecast.

Increasing ocean heat content has been suggested on the basis of theories. Reconstructions (modelling results based on selected scattered measurements) and simulations (modelling results not based on observations) have both shown a significant warming since the year 1970 that increased at an ever faster rate over the 14 years this century. It is shown here that, contrary to this claim, the detailed measurements of the ocean temperature and salinity by the sampling buoys of the ARGO project show only minor changes of temperature and salinity since the early 2000s. The ARGO results cover the ocean layers 0–2000 m except for the North and South Poles. The satellite NSSTC surface air temperature measurements over the world oceans show a global cooling over the last 11 years, and the satellite NSDIC sea ice extent measurements show globally increasing ice coverage over the North and South Poles. The North Pole sea ice is certainly reducing, but over the last 11 years the growth of the South Pole sea ice has more than compensated that loss. The true measurements are in marked contrast to theoretical reconstructions and simulations. This result has a huge implication on coastal management that should be based on observationally derived forecasts rather than “projections” of models lacking validation.