| Ombrotrophic peat bogs are an important ecosystem containing a large amounts of
palaeohydrological information as they derive all of their moisture inputs from the
atmosphere. By exploiting this relationship to the atmosphere, peat bogs have long become an
established source of information about past climate change. Past changes in atmospheric
moisture availability, which in Maritime Canada are closely linked to changes in the North
Atlantic, can be determined by reconstructing change in bog surface wetness (BSW). The
exact processes driving BSW, however, still remain subject of debate and further work
into the autogenic and external processes driving BSW is still needed. The overall
consensus points to summer moisture deficit as the driver of changes in reconstructed
BSW, which in turn is mainly driven by summer precipitation with temperature as a
secondary factor (Charman et al. 2009; Booth, 2010). In order to address the issues
concerning the factors driving BSW, this paper presents a comparison of reconstructed
high-resolution climatic data to instrumental summer and winter climate records for the past
century.
The large majority of work comparing reconstructed records from peat bog proxies to
instrumental data has been carried out using testate amoebae based reconstructions. To
gain a better understanding of the climate parameters driving BSW, analysis of
a wider set of climate-proxies is needed. Results from correlation comparisons
of summer and winter signals from environmental factors such as precipitation,
temperature, effective precipitation and cloudiness with reconstructed data derived from
stable isotopes (δ18O, δ13C), plant macrofossil remains, testate amoebae and peat
humification are presented in order to determine to what extent modern BSW is driven
by external processes and which of these processes are most dominant. In order
to carry out these comparisons, two ombrotrophic plateau bogs from Maritime
Canada (Nordans Pond Bog, Newfoundland and Villagedale, Nova Scotia) were
analysed.
Booth, R.K. 2010. Testing the climate sensitivity of peat-based paleoclimate
reconstructions in mid-continental North America. Quaternary Science Reviews, 29,
720-731.
Charman, D.J., Barber, K.E., Blaauw, M., Langdon, P.G., Mauquoy, D., Daley, T.J.,
Hughes, P.D.M. and Karofeld, E., 2009. Climate drivers for peatland palaeoclimate records.
Quaternary Science Reviews, 28, 1811-1819 |