Should shoreline communities be taking any actions regarding global warming?

Answer 1

Current estimates by NASA are that the Oceans could rise by 8 inches over the next century. Those individuals living within 12 inches of sea level and close to shore have less than 100 years to make changes.

This data may be slightly higher than what we will see as it is based on information over the past decade. Almost no rise has been noted by satellite measurement since 2006. This agrees with data suggesting that the Arctic has also grown by 26% since 2007.

Other projections, from the IPCC are less optimistic, but not been seen to be following the projections.

A:Sea levels have risen 20 centimetres (8 inches) over the course of the twentieth century, but that modest rise is not what is predicted by some groups for the twenty-first century, as the effect is expected to be exponential. The Arctic Monitoring And Assessment Program has recently updated the United Nations estimates to project sea levels to rise between 90 and 150 centimetres by the end of the century. In the last few years, sea levels have risen at an average of around 3 millimetres per year, with about forty per cent of this attributed to melting arctic glaciers, ice caps and the Greenland ice sheet.

One estimate is that as many as 247,000 residential buildings with a value of 63 billion dollars may be at risk from a sea level rise of 110 centimetres. Given the current sea rise, this means that these people have only 550 years before they have issues. Shoreline communities are not in any great rush to make changes.

The assumption that sea levels have been rising at 3 mm a year was proven to be flawed when a peer-reviewed study published that year titled "A new assessment of the error budget of global mean seal level rate estimated by satellite altimetry over 1993-2008" provided evidence that there has been an observed reduction in the prior rate of sea level rise by 2mm/yr from 2005 (a 60% reduction from the 1993 to 2005 rate) to a level of 1mm/yr. This paper shows that the global MSL trend is 3.11±0.6 mm/yr over the whole altimetric period (1993-2008) with a confidence

interval of 90%, but that there was a weak MSL trend observed for the 3 last years (1 mm/yr), consistent with the concurrent La Nina event.