I write in response to the anonymous letter titled ‘Disappointed’ in your September 15 edition.
The mystery correspondent asserts that sea levels are rising by ‘‘only 1.3mm per year’’, and that it will take 1,100 years to achieve a rise of 1.5m. Unfortunately, these assertions are wrong. They are not supported by the observed facts.
The rate of sea level rise has been low, but it is increasing. Mean sea level has risen by some 230mm since 1880. One might call 23cm ‘minimal’, but it is almost a quarter of a metre. In terms of recent sea level rise, if you place a ruler along the long-term trend in the graph, ie between 1889 and about 1990, you will see that the rate of rise has increased since 1990. The increased rate does not look big, but it is there.
The world is getting warmer. The evidence can be found at epa.gov/climate-indicators/ climate-change-indicators-us-and-