The first two years of this decade saw a unique combination of three atmospheric patterns come together over the Indian and Pacific oceans, causing about 300 millimetres more rain than average to fall over the Australian continent. Australia’s unusual soils and topography prevented the majority of this precipitation from running off into the ocean, leading to a halt in the long-term trend of rising sea levels.
To conduct the research, a team of scientists led by John Fasullo of the US National Center for Atmospheric Research in Boulder, Colorado, combined data from three sources: NASA’s GRACE satellites, which make detailed measurements of Earth’s gravitational field, enabling scientists to monitor changes in the mass of continents; the Argo global array of 3,000 free-drifting floats, which measure the temperature and salinity of the upper layers of the oceans; and satellite-based altimeters that are continuously calibrated against a network of tide gauges.
The results showed that the mass in Australia and, to a lesser extent, South America began to increase in 2010 as the continents experienced heavy and persistent rain. At the same time, sea levels began to drop, eventually lowering by about seven millimetres.
This story was published in the October 2013 edition of Geographical Magazine
