Biology Reference
In-Depth Information
Chapter 18
Global Seaweed Biogeography Under
a Changing Climate: The Prospected
Effects of Temperature
Inka Bartsch, Christian Wiencke, and Thomas Laepple
18.1
Introduction
Climate changes and concurrent changes in temperatures, atmospheric CO
2
con-
centration, and other greenhouse gases have often occurred during the earth's
history (Zachos et al.
2008
) and it is well known that biogeographical distribution
patterns of species are directly controlled by climate (Pearson and Dawson
2003
and references therein). Considering only the last 740,000 years, we know of about
eight glaciations associated with strong variations in temperature, precipitation, and
thermohaline circulation worldwide (Augustin et al.
2004
; Knutti et al.
2004
). In the
past century, overall global warming was around 0.8
C (Hansen et al.
2006
).
Changes are particularly strong in polar and cold-temperate regions of the northern
hemisphere (Levitus et al.
2000
; Hansen et al.
2006
). At the western Antarctic
Peninsula a recent rapid regional warming with a sea surface temperature (SST)
increase of 3.7
C century
1
has been recorded (Vaughan et al.
2003
). Massive
retreat of icefronts and glaciers and an increase of melt water production has been
documented since 1956 (Braun and Gossmann
2002
). For the Arctic, a similar
warming trend has been observed over recent decades. Monthly temperature
anomalies can be as large as 3-4
C (Turner et al.
2007
). In cold- and warm-
temperate localities, the reported mean annual temperature increase was as high
I. Bartsch (
*
) C. Wiencke
Department Seaweed Biology, Section Functional Ecology, Alfred Wegener Institute for Polar
and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
e-mail:
inka.bartsch@awi.de
;
christian.wiencke@awi.de
T. Laepple
Section Palaeoclimate Dynamics, Alfred Wegener Institute for Polar and Marine Research,
Bussestraße 24, 27570 Bremerhaven, Germany
e-mail:
thomas.laepple@awi.de
