BACC

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WORKSHOP on BALTEX ASSESSMENT OF CLIMATE CHANGE
for the Baltic Sea basin (BACC) Helsinki,
Finland 19 20 May 2005
BACC Workshop May 2005
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The purpose of the BACC assessment is to
provide the scientific community with an
assessment of ongoing climate change in the
Baltic Sea basin. An important element is the
comparison with the historical past (until about
1800) to provide a framework for the severity and
unusualness of the change. Also changes in
relevant environmental systems, due to climate
change, shall be assessed such as hydrological
change, ecosystems, and ocean waves. The
overall format is similar to the IPCC process,
with author groups for the individual chapters,
an overall policymaker-summary, and a review
process.
BACC structure
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The effort is lead by a Scientific Steering
Committee, which has been formed on an ad-hoc
basis. The members of the SSC are Chair Hans
von Storch DK Jens Hesselbjerg Christensen, Eigil
Kaas, Morten Søndergaard S Markku
Rummukainen, Anders Omstedt, Sten Bergström D
Bodo von Bodungen, Hans von Storch F Jouni
Räisänen P Zbigniew Kundezewicz The BACC
report is part of the ongoing BALTEX
activities. Organisational support by the BALTEX
secretariat (Hans-Jörg Isemer)
BACC structure
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Joint BALTEX - HELCOM Assessment
It was unanimously agreed to establish a joint
BALTEX-HELCOM assessment project. Three bodies or
groups are expected to be involved 1) the BACC
group, represented by Hans von Storch 2) the
Helsinki Commission (HELCOM), represented by
Juha-Markku Leppänen 3) BALTEX as a major
European science programme, represented through
Hartmut Graßl and members of the BSSG, and the
International BALTEX Secretariat. All three
bodies act at different stages of the project.
The overall project management and co-ordination
of actions between the three bodies will be
through Hans-Jörg Isemer, head of the
International BALTEX Secretariat (IBS). The IBS
will also assist in management tasks of the BACC
assessment, in close co-operation with the BACC
SSC and chapter lead authors.
Link to HELCOM
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Six Major Milestones The following six major
milestones (M1 to M6) of the joint BALTEX-HELCOM
assessment project including the suggested time
line and main actors are M1, September 2005
The BACC Assessment material is ready to be
published as a Report. At that time, the report
has already been subject to a scientific review
supported by the BSSG and the review results were
considered for the final report. M2, January
2006 The BACC Assessment material is ready for
printing for an assessment Book to be published
with the Springer Company.
Link to HELCOM
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• M3, March 2006
• The HELCOM Thematic Assessment Report Volume 1 on
  Past
• and Current Climate Change, Detection and
  Attribution (Working title) is ready for
• printing.
• This milestone is expected to require the
  following action steps
• - M1 reached, September 2005
• - The HELCOM Secretariat to extract relevant
  information and establish the 1st draft
• - BACC experts to review the draft
• - The HELCOM Secretariat to finalize the draft
• - BALTEX experts to approve the scientific
  validity of the final draft
• HELCOM to adopt the final draft as a Thematic
  Assessment Report, March 2006.
• M4, May 2006
• A BALTEX-HELCOM International Conference on
  Impacts of climate change on driving forces in
  the Baltic Sea Basin, pressures, state and
  impacts in the marine environment (Working
  title).
• Suggested Conference locations include Helsinki,
  Finland, or Gothenburg, Sweden. The objective of
  the Conference is to lay the scientific base for
  the HELCOM Thematic Assessment Report Volume 2
  (Ecology).
• Conference preparations shall start in May 2005,

Link to HELCOM
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M5, Summer 2006 Establishment of an Expert
Group for Conclusions (climatologists,
ecologists, sociologists, economists) in
preparation for the HELCOM Thematic Assessment
Report Volume 2. Input is expected to be
available in particular from BACC scientists
contributing to chapter 4 of the BACC assessment
book. M6, March 2007 The HELCOM Thematic
Assessment Report Volume 2 is ready for printing.
Completion of this milestone will require close
interaction between the Expert Group (M5) and the
HELCOM Secretariat, along the lines as outlined
for M3, where the scientific review shall not be
confined to the BACC group but should include a
larger group of individuals and disciplines.
Link to HELCOM
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The time schedule is Completing chapters
1.4.2005 Workshop 19/20.May 2005 in
Helsinki Review until 31.5.2005 Revision until
30.6.2005 Finalization until 20.8.2005 Publication
report 1.9.2005 Completion web presentation
1.11.2005 Completion book manuscript open to
revisions
?
BACC time table
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• The assessment will take on the form of a book
  with four chapters
• Overall assessment and summary
• Past and current climate change, detection and
  attribution (atmospheric, ocean, sea-ice,
  land-use, hydrology) Raino Heino and Heikki
  Toumenvirta
• Projections of future climate change Phil
  Graham
• Climate related ecosystem change Bodo von
  Bodungen
• Special emphasis should be given to literature in
  languages other than English, as this body of
  knowledge all too often is not entering the IPCC
  process.
• Springer Verlag has been approached, and has
  responded positively.

BACC Report structure
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Chapter 1 Overall assessment and summary

• to be prepared after completing Chapters 2-4
  by the SCC of BACC

BACC Report structure
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Chapter 2 Past and current climate change,
detection and attribution (atmospheric, ocean,
sea-ice, land-use, hydrology)

• 2. PAST AND CURRENT CLIMATE CHANGE, detection and
  attribution
• 2.1 Executive Summary
• 2.2 Introduction, incl. a brief paleoclimatic
  overview (ca. 10.000 years)
• 2.3 ATMOSPHERIC CHANGES
• Changes in surface climate
• Temperature
• Precipitation
• Atmospheric moisture and clouds
• etc.
• Changes in atmospheric circulation
• Patterns of variability and changes in extreme
  events
• 2.4 TERRESTRIAL CHANGES
• Lakes (temperature, ice cover)
• Rivers incl. runoff
• Snow cover and frozen land
• 2.5 BALTIC SEA
• Water temperature
• Ice
• Sea levels

Ocean waves?.
BACC Report structure
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Chapter 3 Projections of future climate change

• 3.1 Global climate change
• 4.2 Climate change in the Baltic Sea drainage
  basin projections from global climate models
• 4.3 Climate change in the Baltic Sea drainage
  basin projections from regional climate models
• 3.4 Changes in climate variability and extremes
• 3.5 Changes in hydrology
• 3.6 Changes in the Baltic Sea
• 3.7 Changes in the cryosphere
• 3.8 Summary of projections

BACC Report structure
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Chapter 4 Climate related ecosystem change

• 4.2 Human related ecosystem change
• 
  
• 4.2.1 Sources and distribution of nutrients
• 4.2.2 Sources and distribution of organic
  pollutants
• 4.2.3 Sources and distribution of trace metals
• 4.2.4 Agriculture and eutrophication
• 4.2.5 Aquaculture and eutrophication
• 4.2.6 Influence of fisheries
• 4.2.7 Influence of sea traffic
• 4.2.8 Influence of tourism
• 4.2.9 Hot spots
• 4.2.10 Atmospheric input
• 4.3 Climate related marine ecosystem changes
• 4.3.1 Bacteria
• 4.3.2 Phytoplankton
• 4.3.3 Harmful algae blooms
• 4.3.4 Zooplankton

Problem no analysis of terrestrial ecosystem
change.
BACC Report structure
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Needs. Consensus on dissensus

• We need to represent consensus to broaden the
  acceptance. The consensus should be a consensus
  on dissensus, if required. Minority views should
  be listed.
• Possible methodical limitations of reviewed
  studies needs be mentioned, as in Rigid
  statistical analysis has yet to be done to
  separate climate change impacts from other causes
  and understanding better direct and indirect
  influences.
• We should avoid overweighting individual papers,
  which are not (yet) supported by independent
  analysis by other parties.

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Needs Detection and attribution

• We need to first document the changes, then
  address whether these are unlikely to be a
  possible swing in the natural sequence of events
  (Detection rejecting the null hypothesis of no
  signal) and finally select from a series of
  different explanations the most plausible ones
  (attribution).
• We need to document changes until very recently,
  as there has been a trend reversal with the NAO
  in the late 1990s.

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Needs Homogeneity of data

• Data must be examined which processes may be
  influence, or even contaminate, the data series
  (homogeneity).
• The earlier warming period (in Fennoscandia
  between 1870-1940) must be considered as well.

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Need to define significant trend

• When we use, as is often done, the Mann-Kendall
  test for trends what is the model assumed and
  what is the null hypothesis?
• Usually the model used is that the data
  generating process is apart of a possible trend
  white in time. This is often not valid in our
  applications (see low-frequency variability of
  NAO)
• The null hyothesis is that an observed trend is
  often found in a series of n numbers made up of
  white/red noise. Alternative series is not
  white/red or nonzero trend no evidence for
  ongoing trend.
• Do we need an appendix in the book on that?

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Need to agree on terminology

• Climate statistics of weather
• Regime shift ?
• Scenario plausible, possible, consistent but
  not necessarily probable future

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Presentation

• No normative statements This is good should be
  avoided, but this is good for the quality of the
  water is valid.
• Sloppy language should be avoided, as e.g., in -
  significant global warming may change the
  species composition global warming changes
  nothing, local warming does. Thus, we need to
  first show effect gt local geophysical
  conditions, then local conditions gt anthropogenic
  causes,- The summers had a very low average
  sunshine duration and therefore no blooms
  developed. is this link beyond doubt or may
  other processes be involved?

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Thursday, 19 May 2005 9.00 Opening and
Introduction Hans von Storch, BACC SSC
chairman Representative of HELCOM Others tbd
Presentation of Chapter Contents and
Discussion The present chapter contents will be
reviewed by the respective chapter lead author.
The material presented will be open for
discussion by all participants. 9.30 Chapter 2
Past and Current Climate Change Speakers Raino
Heino and Heikki Tuomenvirta Discussion Break 11.3
0 Chapter 3 Projections of Climate
Change Speaker Phil Graham Discussion 13.00 Lunc
h Presentation of Chapter Contents and Discussion
(continued) 14.00 Chapter 4 Climate-related
Ecosystem Change Speaker Bodo von
Bodungen Discussion 15.00 Break Breakout
sessions Authors of each chapter will convene in
separate chapter sessions to discuss on the
outcome of the morning session and implications
for the material to be included in the next draft
chapter version. Breakout sessions are expected
to continue throughout the afternoon.
19.00 Dinner
BACC Workshop May 2005
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Friday, 20 May 2005 9.00 Plenary Summary
Presentation of Breakout Sessions The chapter
lead authors will review discussions and
conclusions of the breakout sessions. A final
overview on the material and findings of chapters
2 to 4 are expected to be given.
10.30 Break 11.00 Presentation of the
Introduction and Summary chapters Speaker Hans
von Storch Discussion 13.00 Lunch 14.00 Fina
l discussionWrap up of the workshopFuture
actions and time lineAny other
business 15.00 Closing of the workshop
BACC Workshop May 2005
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(No Transcript)
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Chapter 4 overlap
4.1.1 The late Quaternary development of the
Baltic Sea 4.1.3 Oceanographic peculiarities
4.1.4 Climate variability and steady-state
sensitivity 4.1.7 Water cycle in the Baltic
Sea 4.3.1. The physical system
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Chap 4, writing team

• Chapter 4 climate related eco- (and human?)
  system change
• Ben Smith, Martin Sykes, B. v. Bodungen, Kay
  Emeis, Ilppo Vuorinen, Kristine Garde Ulo Mander
  Tumas Rimvydas
• Reserve
• C. Humborg, Lars Rahm, Joachim Dippner, Günther
  Nausch, Thomas Leipe Jürgen Alheit.(all IOW),
• Sergei Olenin (Lithauen), Andris Andrushaitis
  (Lettland),
• Weslawski, Andrzej Kedziora, Maciel Zalewski (PL)
• Boris Faschchevskiy (BEL),
• Erik Bonsdorff (Fi).
• Ragnar Elmgre, Sture Hansson, Bo Gustafsson, Edna
  Granéli (S)