As sea level has changed, so has the way we measure it. Here’s a look at some of the technologies climate and marine scientists have used to track Earth’s tides and global sea level over the past two centuries.
Across the globe, changes in salinity over time generally match changes in precipitation: places where rainfall declines become saltier, while places where rainfall increases become fresher. Where did saltiness change over the past decade?
Through June, the eastern Pacific was warmer than average, but the lack of a strong gradient in sea surface temperature anomalies between the eastern and western Pacific may have kept the atmosphere from getting in sync with the developing El Niño.
The globally averaged sea surface temperature in 2013 was among the 10 highest on record, with the North Pacific reaching an historic high temperature. ENSO-neutral conditions and a negative Pacific Decadal Oscillation pattern had the largest impacts on global sea surface temperature in 2013.
Large-scale patterns of sea surface salinity in 2013 mirrored the overall trend seen from 2004 to 2013: salty, dry areas are becoming increasingly salty, and fresher areas are becoming increasingly fresh.
Upper ocean heat content has increased significantly over the past two decades. An estimated 70 percent of the excess heat has accumulated in the top 2,000 feet of the ocean, and the rest has flowed into deeper ocean layers.
In 2013, global average sea level was 1.5 inches above the 1993-2010 average, which is the highest yearly average in the satellite record (1993-present). Overall, sea level continues to rise at a rate of one-eighth of an inch per year.
Why on Earth are climate scientists so interested in the West Antarctic ice sheet? This remote region of the seventh continent has been the subject of many recent research explorations--the results of which have been described in the news with words like “collapse,” “irreversible,” and “huge.”
For the billions of people in Asia who depend on the Indian Monsoon for the majority of their yearly rainfall, the precise location where the Pacific warms during El Niño may be the difference between a relatively normal year and a devastating drought.