The Center for Operational Oceanographic Products and Services (CO-OPS) has redesigned the Sea Level Trends section of its website https://tidesandcurrents.noaa.gov/sltrends/. We have also automated the generation and monthly updating of the graphics on the site. Although the look of the site is the same, several enhancements will make the site more useful to the public. Among these are:
Up to now, CO-OPS has displayed the trends documented in NOAA Technical Report NOS CO-OPS 53, "Sea Level Variations of the United States 1854-2006" on its website. Since 2011, CO-OPS has been recalculating new sea level trends for all operating stations every year using each additional year of data, but only displaying them on an Updated Mean Sea Level Trends page for each station for comparison with previously-calculated trends.
Beginning now, the newly-calculated trend will also be updated on all the maps and be displayed on each station's main sea level trend page. A newly-calculated seasonal cycle will also be displayed on each station's average seasonal cycle page. The interannual variations plots and the anomaly maps will now be based on the subtraction of the latest calculated trend and seasonal cycle. Therefore, the numbers on the plots will change slightly from year to year depending on the new data. However, since the calculated trends and average seasonal cycles are based on at least 30 years of data, an additional year of data can only make small changes to the numbers. As of now, the values displayed on the website are based on all data up to the end of 2013. CO-OPS will likely introduce newly-calculated trends in April of each future year, after all the previous year's data has been verified.