Ecoinformatics Problems of Global Climate Change - New Ecoinformatics Tools in Environmental Science: Applications and Decision-making - page 390

increasing. Between 1870 and 2004, global average sea levels rose 195 mm (7.7 in)
(Church and White 2006). From 1950 to 2009, measurements show an average
annual rise in sea level of 1.7

± 0.3 mm per year, with satellite data showing a rise

of 3.3 0.4 mm per year from 1993 to 2009 (Nicholls et al. 2010), a faster rate of

increase than previously estimated (IPCC 2007). For at least the last 100 years, sea
level has been rising at an average rate of about 1.8 mm per year. Most of this rise
can be attributed to the increase in temperature of the sea and the resulting slight
thermal expansion of the upper 500 m of sea water.
Operative data about sea level is delivered by the Global Sea Level Observing
System (GLOSS) that aims at the establishment of high quality global and regional
sea level networks for application to climate, oceanographic and coastal sea level
research. The main component of GLOSS is the Global Core Network (GCN) of 290
sea level stations around the world for long term climate change and oceanographic
sea level monitoring (Fig. 5.9 ). Figures 5.10 and 5.11 characterize data about sea
level dynamics. Figure 5.10 shows the sea level change as a function of temperature.
Hourly, daily and monthly sea level data are provided and hosted by Joint Archive
for Sea level (JASL)-NODC and the University of Hawaii Sea Level Center
(UHSLC) from stations in tropical and subtropical areas of the Paci

±

c, Atlantic, and
Indian Oceans. Most data are from tide gauges but some data are delivered from
bottom-mounted pressure gauges. Global sea level data are also delivered from
satellite altimeter data ( http://data.nodc.noaa.gov/accession/0053056 ) .
Levitus et al. (2001) analyzed data on the warming of some components of the
climatic system during the second half of the 20th century. These data were derived
from the growth of the heat content of the atmosphere and ocean as well as from
estimates of the heat losses due to melting of some components of the cryosphere.
These findings have led to the conclusion that the heat content of the atmosphere

and ocean is rising. The growth of the heat content in the 3-km ocean layer between