| Clouds,
vegetation, diffuse light, shade and the CO2 flux
Thursday 1 August 2002, 11 AM
CSIRO Atmospheric Research, Melbourne, Victoria
Presented by Michael Roderick, Graham Farquhar,
Sandra Berry, Ian Noble
CRC for Greenhouse Accounting, Research School of Biological Sciences,
The Australian National University
Because of increased clouds and/or aerosols, there has been a marked
increase in diffuse light, especially in the northern hemisphere,
over the last 50 years. That is important because when light is
diffuse there is minimal shade and whole canopy photosynthesis is
very sensitive to shade, and hence to an changes in the amount of
diffuse light. In this talk, we show how this fundamental plant-environment
interaction explains many long observed trends. We also show how
to use these relations (when combined with satellite data) to develop
a generic framework for estimating continental and global scale
plant gross productivity. Finally, we use the theory to show that
the anomalous decline in atmospheric CO2 observed after the Mt Pinatubo
eruption (June 1991) was about the same magnitude as predicted by
the theory, because forward scattering by sulphate aerosols resulted
in a large (and transient) increase in diffuse light immediately
after the eruption.
For more details, read the paper
(in PDF).
Ground
Based Remote Sensing of Cirrus Clouds in the Tropical Western Pacific
Friday 2 August 2002, 11 AM
CSIRO Atmospheric Research, Melbourne, Victoria
Presented by Tom Ackerman, Pacific Northwest
National Laboratory, USA
The Atmospheric Radiation Measurement (ARM) Program, sponsored
by the US Department of Energy, maintains a ground-based remote
sensing site at Nauru and at Manus, PNG. We have used approximately
a year of data from each of these sites to derive the radiative
and macrophysical properties of tropical cirrus clouds. combining
either lidar or radar measurements with infrared radiance measurements
provides independent retrievals of cloud height and visible optical
depth. We find that the millimeter cloud radar does not detect cirrus
clouds that have a cloud base higher than 15 km. These clouds comprise
about 15% of the clouds detected by the lidar. Lidar and radar cloud
heights are in good agreement for layers below 15 km. Analysis of
observed cirrus macrophysical and radiative properties suggests
that there are essentially two different populations of cirrus existing
in the tropical western Pacific: (1) high, thin, laminar cirrus
with cloud bases higher than 15 km, and (2) lower, physically thicker,
more structured cirrus clouds below 15 km. The differences in these
two populations are most likely linked to their formation mechanisms,
with the upper clouds produces by large-scale dynamics and the lower
clouds by convection. The presence of these high, thin clouds has
implications for, amongst other things, stratospheric-tropospheric
exchange and satellite remote sensing.
Dealing
with Kyoto and Non-Kyoto Markets
Melbourne, 8th August 2002
Venue: Melbourne Business School
200 Leicester Street, Carlton, Victoria, Australia
The Australasian
Emissions Trading Forum (AETF) will present 'Dealing with Kyoto
and Non-Kyoto Markets" in Melbourne, Australia on 8 August
2002.
A one day seminar
to explore issues of business engagement with countries inside and
outside the Kyoto bloc after the Kyoto Protocol comes into force.
This event will involve discussion of the status of Australian greenhouse
policy; international and domestic emissions trading and policy
developments; Australia’s trading relationship with Japan, the US
and others; Carbon sequestration, accounting and trading issues.
Speakers include Dr
Chris Mitchell, Actg. CEO, CRC for Greenhouse Accounting (CRC
GA), and Ms
Louise Drolz, Manager, Environmental Markets, Tullett &
Tokyo Liberty P/L and Member of the CRC GA Advisory Council.
Other key government and industry speakers include:
- Candy Broad, Minister for Energy and Resources, Victoria
- Roger Beale, Secretary, Environment Australia
- Tony Beck/Malcolm Gray, AETF Coordinators
- Peter Heyward, Manager, Climate Change, Dept. of Foreign Affairs
& Trade
- Clinton Watkins, Development Manager & Economist, EcoCarbon
Inc.
- James Shevlin, Executive Manager, Australian Greenhouse Office
- Katy Brady, Senior Market Development Analyst, SEDA
Cost: $440 incl. GST.
For details of the program see http://www.aetf.net.au/topics.html?DocumentName=Events.html
For registration information see the Events page on the AETF
website or click here.
Presentations from the seminar are available here.
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