Geoscience Reference
In-Depth Information
Dates
Sources
Reliability
1335-1986
R. H. Hayes and J. Hurst, A History of Hutton-le-Hole(1989)
These use primary sources and living
1587-1905
A. Hollings, A History of Goathland(1972)
memories. They are area-specific, reliable,
1782-1945
M. Hartley and J. Ingilby, Life in the Moorlands of North-
and discuss weather and landscape, and
east Yorkshire(1972)
give good background information
1860-1929
R. H. Hayes, A History of Rosedale(1971)
There are, now, not only widely accepted physical laws and
standards on which we base our reconstructions but also
international commissions across a number of related
scientific fields which develop unified time scales and
correlations of events. All this is most timely, given the
nature of the rapid, global climate and environmental
changes we now face and the call for unified international
responses. Earth's present and reconstructed past environ-
ments provide our best analogues for the future. Only time
and hindsight will tell whether or not we are now leaving
the Holocene for the Anthropocene - for which there may
be no analogues!
CONCLUSION
Our understanding of what we now call Earth Systems
processes and sense of geological time scales have drawn
geologists, physical geographers and environmental
scientists together to unravel the sequence and character
of past environments - the Earth system history - which
have shaped the planet we inhabit today. The reconstruc-
tion of that history depends on the recognition and
deciphering of environmental signatures that constitute
proxy records of long-gone events and conditions, linked
with the existence of modern analogues as far as possible.
KEY POINTS
1
The geosphere, atmosphere and biosphere have undergone continuous and interlinked change throughout
Earth's history. We can find evidence of this in the geological record contained in exposed, surface rocks,
unconsolidated sediments and fossils, and through subsurface coring and remote sensing technology,
which enable us to reconstruct past environments.
2
Past processes left their signature in the character and content of these Earth materials as proxies from
which we now infer a range of environmental conditions at, and since, the time of their formation. Correct
interpretation depends on uniformitarian principles which assume that present-day environments and
processes provide good analogues for the past.
3
Laws of stratigraphy, and correlation between different regions, enable us to construct a relative time scale
and sequence of past events. Understanding the absolute age and rates of events and environmental
processes is heavily dependent on radiometric dating and other sophisticated, micro-biogeochemical
analyses. Stable isotope stratigraphy permits further age correlation and allows us to tune events
represented in a wide range of environmental records.
4
The landscape and vegetation of long-settled European countries like Britain have been greatly modified
by prehistoric and historic civilizations. Therefore good interpretations of climate and land use changes
depend upon parallel studies of the archaeology of regions as well as their physical geography. Peat bogs
provide good evidence of recent climate, natural and anthropogenic vegetation change through their
preservation of identifiable fossil pollen and spores and because their state of humification reflects their
surface wetness
5
Documents also provide invaluable sources of recent environmental change but have to be read with care.
Their reliability is variable, depending upon the purpose of the document and whether it is based on
scientifically accurate data. Secondary sources are often good, with records from memory of extreme
climatic events being especially useful.
