Temperatures have increased
Annual and seasonal maximum temperatures have increased in Tarawa since 1950. Maximum temperatures have increased at a rate of 0.18 degrees Celsius per decade. These temperature increases are consistent with the global pattern of warming.
Annual rainfall has increased
Data since 1951 for Kirimati show a clear increasing trend in annual and wet season rainfall, but no trend in annual and wet season rainfall, but no trend in the dry season. At Tarawa, rainfall data show no clear trends. Over this period, there has been substantial variation in rainfall from year to year at both sites.
Sea level has risen
As ocean water warms it expands causing the sea level to rise, the melting of glaciers and ice sheets also contributes to sea-level rise.
Instruments mounted on satellites and tide gauges are used to measure sea level. Satellite data indicate the sea level has risen across Kiribati by 1 – 4mm per year since 1993, compared to the global average of 2.8 – 3.6 mm per year. Sea level rise naturally fluctuates from year to year and decade to decade as a result of phenomena such as the El Nino-Southern Oscillation.
Ocean acidification has been increasing
About one quarter of the carbon dioxide emitted from human activities each year is absorbed by the oceans. As the extra carbon dioxide reacts with sea water it causes the ocean to become slightly more acidic. This impacts the growth of corals and organisms that construct their skeletons from carbonate minerals. These species are critical to the balance of tropical reef ecosystems. Data show that since the 18th century the level of ocean acidification has been slowly increasing in Kiribati’s waters.
Information on this page has been sourced on behalf of the Kiribati Meteorology Service and with kind permission from Australian Bureau of Meteorology and CSIRO, 2011.Current and future climate of Kiribati. Visit www.pacificclimatechangescience.