2.1.6 Climate of the past several centuries
Instrumental records of weather for Queensland are of a high
quality due to the foresight and tenacity of the first Government
Meteorologist, Clement Wragge, working in the late 19th
century. These records extend back little more than a century which
is a relatively short time to assess the long-term natural
variability of climate. To examine variations of climate before the
mid-19th century proxy climate records are required eg
tree rings, ice cores. For shallow-water tropical ocean regions a
wealth of proxy climate and environmental information is locked away
in the annual bands of certain massive coral skeletons which can
live to be 700-800 years old (Barnes & Lough, 1996). A
reconstruction of Burdekin River runoff from luminescent bands in
corals from Havannah and Pandora Reefs (see Isdale et al.
1998) shows much greater variations of river flow than have been
experienced in the 20th century (Figure 6). A
reconstruction of sea-surface temperature from the calcification
rates of corals along the GBR (Lough & Barnes, 1997) also shows
larger excursions of temperature than experienced in the
20th century (Figure 7). These proxy records contain many
sources of error and more records are required to refine the climate
histories they suggest.
Reconstructed Burdekin River runoff, 1644-1980, from luminescence in
coral skeletons. Thick line is 30-year gaussian filter to emphasize
multi-decadal variability (from Isdale et al. 1998).
Reconstructed sea surface temperature anomalies for the Great
Barrier Reef from calcification rates in 10 corals. Thick blue line
is 30-year gaussian filter to emphasise multi-decadal variability
(from Lough & Barnes, 1997).