Wednesday, May 16, 2012


date: Tue, 23 Jun 1998 16:44:21 +0200
from: Frank Oldfield <>
subject: PAGES FOCUS 3

Dear colleagues,

This is a hasty first draft (both as a Word attachment and as unformatted
e-mail text) of notes on our recently agreed plans for the development of
Focus 3 (Human interactions in past environmental changes)within PAGES.
Those of you who were at the meeting in Pallanza will recognize it as an
expansion of the preliminary ideas presented and endorsed there. My
intention is to circulate a revised version of this text, as a Newsletter
item and via e-mail, as soon as possible after my return to Bern, July 18.
To that end, I would very much welcome any observations you would like to
make, any suggestions for changes or improvements and any ideas about key
people to contact.

With best wishes,



PAGES Focus 3:
A new initiative on past human impacts

The main thrust of the PAGES program hitherto has been towards a better
understanding of past climate change and its implications for the future.
Focus 3, which is concerned with the past impact of human activity on
ecological and hydrological systems, has never been fully articulated,
though significant progress has been made in one specific area - human
impact on fluvial systems- thanks to the efforts of Bon Wasson. At the
recent PAGES SSC meeting, held in Pallanza, N. Italy, June 19-21, an
overall strategy was presented and endorsed. This strategy envisages seven
interlinked themes as set out below. Their coordination and their
articulation as PAGES Activities and Tasks will be the responsibility of a
small steering group, yet to be identified. The goals of the
paleoscientists involved in this exercise will include the following:

1. To define, promote and pursue areas of shared interest between PAGES and
other IGBP project elements.
2. To contribute fully to the PAGES, and eventually IGBP, syntheses
currently being undertaken
3. To lay the basis for the further development of these themes during the
next stage of IGBP's work from the year 2000 onwards.

The themes briefly noted below have yet to be fully defined and, in some
cases, leaders have yet to be identified. A workshop to develop science and
implementation plans will be held in late 98/ early 99. Meanwhile,
colleagues interested in contributing to this aspect of PAGES work are
invited to contact the IPO and its Executive Director
( who will be responsible for the overall
coordination of Focus 3 in its early stages.


The themes envisaged at this stage are as follows:

1. The history of greenhouse gas exchanges between the terrestrial
biosphere and atmosphere.
These exchanges are of major concern in relation to understanding present
day and future carbon dioxide and methane fluxes and budgets. There is an
urgent need to improve our insight into the way past changes in land cover
and hydrology have affected the fluxes and reservoirs over the non-marine
part of the biosphere. The task spans a range of themes, from the past
carbon balance in wetlands, to the impact of both deforestation and
reforestation on CO2 fluxes at both regional and global scales. One major
advantage of undertaking this task for the past lies in the way in which it
can be linked, on a range of timescales, to the traced gas record in ice
cores. The task is seen as contributing to the GAIM led 'paleo-trace-gas
challenge' and as helping to forge links between PAGES and other project
elements such as GCTE and BAHC especially.
2. Past biogeochemical fluxes within fluvial systems.
This theme is closely linked to the next two and it embraces the concerns
of the BLOP report (proper title goes here) as well as one of the main
tasks for PAGES within the IGBP inter project initiative on 'Continental
Aquatic Systems.' It is also currently being actively promoted by the
LUCIFS project (Land Use and Climate Impacts on Fluvial Systems during the
Period of Agriculture) led by Bob Wasson. Further information on this
project is available via�
3. The historical context of multiple threats to both aquatic and
terrestrial ecosystems.
Climate variability and future climate change are only one factor, and
perhaps often not the most important factor, in the complex of threats
facing both terrestrial and aquatic ecosystems. Studies of soil erosion,
surface water acidification and eutrophication as well as the amelioration
of the effects of these processes requires that they be set in historical
context. Lake sediments serve as archives of all these processes, including
the more recently recognized threats posed by increased nitrogen deposition
and contamination by a range of 'new' compounds. Well-focused paleodata is
essential for setting present day monitoring in time context as well as for
model evaluation. This may be best illustrated by work on the history of
acidification and eutrophication carried out worldwide over the last two to
three decades in response to urgent environmental problems.
4. Historical perspectives on water quality/lake ecosystems.
This theme is closely linked to the ones above and reflects a significant
part of PAGES input to the IGBP 'Continental Aquatic Systems' inter-project
already mentioned. It has now been accepted as a PAGES Activity within
Focus 3, led by Rick Battarbee.
5. Non-linear ecosystem changes in the geologically recent past.
Many researchers within the IGBP community rely on developing models of
change through time by postulating temporal linkages between the different
elements in a spatial mosaic. This approach has both strengths and
weaknesses. One of the latter arises from the problem of rapid non-linear
shifts in ecosystem function once key thresholds (e.g. in water retention
or nutrient cycling) are transgressed. The paleo record is rich in evidence
for such changes and there is a need to generate a better awareness of
their causes and effects especially where the record from the past can be
used to improve our understanding of highly stressed ecosystems at the
present day.
6. Global and regional time-slice reconstructions
The well-developed BIOME 6000 program is an example of this type of
activity. The need now is for reconstructions, especially of terrestrial
vegetation and land cover, for the last 200 - 300 years, the period of
rapidly accelerating change and human impact. This will call for an
integration of paleorecords from sources as diverse as pollen analyses and
past tax returns, and it will contribute directly to the needs of GCTE and
LUCC, as well as to the theme identified under 1 above. It will be one of
the themes in a joint PAGES-LUCC workshop planned for November, 1998.

7. The historical context of contemporary and future changes in areas of
high 'value' and/or vulnerability.
In several cases, LUCC and GCTE, for example, envision a detailed focus on
a specific region. In one case at least, the LBA in Amazonia, there is a
coordinated IGBP activity across a wide range of Project Elements. Where
such regions are defined, whether as transects across ecotones or as areas
of concentrated research, PAGES can play an important role in placing
changes in present day ecosystems and in the hydrology of the region in a
longer time perspective. This can provide a dynamic baseline for future
monitoring, an insight into processes operating on timescales longer than
the span of available direct observations, and a quantitative estimate of
the range of natural climate variability in the recent past. The capacity
to do this will differ in different parts of the world, since it depends on
the presence of suitable paleo-archives, ideally high resolution ones with
records that come through continuously to the present day. Full
exploitation of these rests on an acknowledgement that PAGES shares the
task of understanding processes rather than simply providing 'historical
reconstructions'. Many key processes in the climate system, at the
ecosystem level and within hydrological systems, operate on decadal to
century timescales. Establishing their functioning and their effects has an
important role to play in understanding present and future earth system
dynamics on all spatial scales.


The themes outlined above must be a crucial part of PAGES' and IGBP's
overall strategy for several reasons. From the PAGES standpoint, we have to
realize that no amount of paleoreconstruction can fully prepare us for
future changes and future impacts operating on the present day landscape.
The effects of human activity over the last ca. 200 years have led to
transformations much more significant than those resulting from climate
change. They have endowed us with a 'no-analogue' biosphere as the canvas
upon which future climate changes and human activities will interact.
Moreover, this no-analogue biosphere is the point of departure for the
future part of the global experiment to which increasing greenhouse gas
concentrations in the atmosphere will contribute. To consider this complex
and rapidly changing canvas without regard to its antecedents is not a
realistic enterprise. PAGES FOCUS 3 is therefore a research domain within
which, as the messages from the past overlap the observations of the
present, we may hope to develop and optimize the interactions between many
aspects of IGBP's endeavors. Human activities are as much drivers of
contemporary and future environmental change as are anticipated changes in
climate. The interplay between the two types of forcing is of vital concern
and the history of their interaction is ignored at our peril, especially in
the realm of future impacts and their integrated assessment. In this
respect, the proposed FOCUS 3 initiatives are a response to human needs as
well as to the emerging research agendas of national and international
funding agencies.


The various themes outlined above are closely interwoven and will require a
coordinated network approach for their realization. We can illustrate this
simply by identifying the key archives for many of the themes, namely
lacustrine and high resolution, near-shore marine sediment records of
changing land cover, associated biogeochemical fluxes and their impacts on
both terrestrial and aquatic ecosystem structure and function. There are
other vital linking concerns. The concept of sustainability has no
realistic meaning unless it accommodates what we know of past climate
variability, human activities and the consequences of their interaction.
Equally, development of the themes proposed is a prerequisite for model
evaluation, which, in turn serves to improve predictive capability.

The first task is to identify a cohort of potential participants ready to
share the challenges implicit in this proposal. An immense volume of highly
relevant data already exists. One of our main roles must be to evaluate,
filter, coordinate and systematize what is already known, as it bears on
the key issues already partly identified in the outlines above. This
'prospectus' therefore comes with a request that all interested scientists
contact us in the PAGES Office in Bern with an outline of their own
perspectives and of the potential roles they may be prepared to play. In
some cases, as for example in the case of aquatic ecosystems and of human
impact on fluvial systems, the leaders (Rick Battarbee and Bob Wasson
respectively) have been identified and work is already in progress. In
other cases, there is a need to identify those who will be prepared to play
a crucial, active role in coordination and leadership. Again, we are
putting this proposal forward in an effort to solicit both potential
volunteers and nominees. By joining in such an effort, our hope is that
you will not only contribute to making the best possible use of current
knowledge and ongoing research; you will also be helping to define key
aspects of the global change research agenda for the future.

Attachment Converted: "c:\eudora\attach\focus31.doc"
Frank Oldfield

Executive Director
Barenplatz 2
CH-3011 Bern, Switzerland


Phone: +41 31 312 3133; Fax: +41 31 312 3168

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