Transcript Catalytic stratospheric ozone destruction

Research Needs*†
We are now in the “accountability” phase of MP, where
we must closely monitor the layer through the sensitive
recovery period.
- Are our actions having the desired effects?
- Is the ozone layer recovering?
Vigilance is essential during adaptation to and mitigation
of climate change.
- Are there any unintended consequences to the ozone
layer?
†Starting from Ravi’s talk on Sunday
[*Adapted from: Synthesis and Assessment Product 2.4: Trends in Emissions of Ozone Depleting Substances,
Ozone Layer Recovery, and Implications for UV Radiation Exposure]
Ultraviolet
radiation change
Global
ozone
change
Ozone-depleting
chlorine and
bromine in the
stratosphere
ODS
production
Scientific Findings
(a)
ODS production
(b)
ODS in the atmosphere
Ozone levelsmeasured and
predicted
(c)
(d)
1980
Now
2100
UV levelsmeasured and
predicted
“There is even stronger evidence since the 2002
Assessment that the Montreal Protocol is working”
Return of ozone to pre-1980 levels
ODS are decreasing & the ozone layer is starting its recovery
Climate change and ODSs will affect the future of ozone layer
Decreases in ODS emissions already achieved by MP is the
dominant factor in return to pre-1980 values
Global ozone layer (60oS-60oN) is
expected to recover to pre-1980
values around 2050
But failure to continue compliance with the MP could
delay or even prevent the recovery of the ozone layer
A balanced programme of
atmospheric observations,
laboratory measurements,
modelling and data analysis.
Particular plea for (continued) collection
of long-term measurements for science.
Testing convection?
Pacific
Samoa
14ºS
Africa/Indian
Ocean
Reunion I
21ºS
Atlantic
Ascension
7ºS
Continental
Africa
Niamey
12 º N
O3
July sondes
2006
SHADOZ + SCOUT-O3
AMMA data
Gaps in Our Knowledge and Future Needs
1. Continued atmospheric observations
- Ozone
- ODS
- New releases (ascertain their ozone friendliness!)
- UV and its changes
Needs recognised here include
• the absolute necessity to maintain high quality GB
observations
• concerns about satellite data (gaps) - hi-res ozone
profiles; ODS (Cly, Bry) evolution; water vapour;
ozone diagnostics.
Gaps and needs, continued
2. Understanding the processes that impact ozone layer
- chemical processes
Need for updated lab measurements, e.g. ClO dimer, ODS lifetimes
- dynamical processes
e.g., strengthening BD circulation; ODS lifetimes
- New releases
3. Global models
- Deal with stratosphere as an integral part of the Earth system
- Enable better prediction of recovery and accounting
CCMVal activity
4. Reporting and documentation
- Better accounting for ODSs and related chemicals
Important that we maximise use of all resources infrastructure, capital and human.
Overlap between programmes?
Overlap of data bases?
Trust fund/capacity building?