Transcript Tackling Climate Change: The role of the engineer

Climate Change,
the Kyoto Protocol
and Civil Engineering
Dr Stuart Parkinson
http://www.sgr.org.uk
The basic science…
• Natural ‘greenhouse effect’
– Sun’s heat trapped by greenhouse gases (GHGs)
• Human emissions of GHGs trapping more heat
• This ‘global warming’ is leading to changes in
climate
• Assessment of scale of the problem provided
by Intergovernmental Panel on Climate
Change (IPCC)
Defining the climate problem
• Present global temperatures
– are 0.7C higher than 100y ago
– are higher than at any time in the last 1000y
• Predicted global temperatures in 2100
– will be between 1.4 and 5.8C higher than 1990
– will increase faster than at any time since the
transition from last Ice Age (10,000y ago)
Lead to major changes in climate
Variations of the Earth’s Surface Temperature:
1000 to 2100
• 1000 to 1861, N.
Hemisphere, proxy data;
• 1861 to 2000 Global,
Instrumental;
• 2000 to 2100, SRES
projections
Source: IPCC (2001)
Reliability of scientific assessment
• Physics of Greenhouse Effect well understood
(observations of Earth, Mars, Venus)
• Wide range of data on past climate
– eg ‘ice cores’ show carbon dioxide and temperature
have varied together over past 420,000y
• Climate models calibrated on past changes
used to predict future changes
CO2 versus temperature
Human emissions of GHGs
• Carbon dioxide (60% of warming effect)
• from burning coal, oil, gas for energy; and deforestation
• Methane (20%)
• from gas leaks, livestock, paddy fields
• ‘F’ gases, eg HFCs (14%)
• from fridges, air-conditioning, electronics industry etc
• Nitrous oxide (6%)
• from nylon industry, agriculture etc
What will be the effects?
• Sea level rise – approx 0.5m by 2100
• ‘More energetic hydrological cycle’
– More severe weather, eg storms, floods in some
areas, with droughts in others
• Large regional changes in climate
– Jeopardising food, water supplies
• Risk of dramatic/ irreversible climate shifts
• Poorer countries most vulnerable
Possible impacts
Recent UK Meteorological Office study…
• Increase in people facing ‘water stress’
– extra 3 billion (four-fold increase) by 2080
• Increase in people facing malaria
– extra 290 million by 2080
• Increase in people facing flooding
– Eight-fold increase by 2080
• Substantial die-back of tropical forests
Framework Convention on
Climate Change (FCCC)
• Agreed at Rio Earth Summit in 1992
• Aim: ‘to prevent dangerous anthropogenic
interference with the climate system’
• Method: control of greenhouse gas (GHG)
emissions
• Industrialised countries agreed to act first
• 190 countries now ratified
Kyoto Protocol (KP)
• Agreed in 1997
• Set targets and timetables for control of
emissions of 6 GHGs in 38 industrialised
countries (and EU)
• Combined target equals 5.2% reduction in
net emissions between 1990 and 2008-2012
• Allowed for use of carbon trading, carbon
sinks (forestry etc)
KP Targets
• EU: 8% overall cut compared to 1990
– UK: 12.5% cut; Germany: 21% cut; France: 0%
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USA: 7% cut
Japan: 6% cut
most Eastern European countries: 8% cut
Russia: 0%
Australia: 8% increase
KP current status
• Entered into force on 16th February, 2005
• Ratified by 150 countries
• USA, Australia not ratified for ‘economic’
reasons
Tackling CO2 emissions
• Change energy production
– Fuel switching, renewables, cogeneration,
carbon capture and storage, nuclear?
• Preserve and improve forestry
– Conservation, reforestation, afforestation
• Improve energy efficiency
– Buildings/ transport/ industrial sectors
Improving energy efficiency
in buildings sector
Buildings
Global CO2
emissions in
1990
(MtC/y)
Annual
growth rate
(1990-95)
Potential
reduction in
2010
(MtC/y)
Potential
reduction in
2020
(MtC/y)
1650
1.0%
700-750
1,000-1,100
Notes
Buildings emissions are approx 25% of total global CO2 emissions from all sectors
Figures include construction and use of buildings
Most reductions available at negative net direct cost
Source: IPCC (2001)
Technical measures
• Over 200 technical energy efficiency
measures have been identified in buildings
sector
• Main areas
– insulation (roofs/ walls/ windows); efficient
space heating/ water heating/ ventilation;
efficient appliances/ lighting; environmental
design; energy management systems; local
energy sources (eg Bipv)
Technical measures
• Space heating is largest energy user
• ‘Integrated building design’ reduces energy
use by 40% on average
• Use of energy efficient appliances/ lighting
reduces energy use by 40% on average
• ‘Aggressive implementation’ can lead to
major GHG reductions and be cost-saving
UK efforts
• Gov estimates UK will beat KP target
– GHG emissions reduced by 21% by 2010
• Buildings sector
– Business
• UK ETS; climate change levy; CC agreements
– Domestic
• Energy Efficiency Action Plan; promotion of new
technologies
Conclusions
• Climate change resulting from human
activity is an extremely serious global threat
• Buildings sector is a major source of GHG
emissions
• Environmental action by the civil
engineering sector is both cost-effective and
can make a very large contribution to
tackling the problem