CO2 1895 Arrhenius ….. 1938 Callendar 1979 WCC-1 1988 , 1990 UNGA
1957 Revelle 1988 Toronto 1992 UNFC-CC
Reasons for the very long time period in case of CO2/ghg emissions?
longer time for "enough" sci. certainty, less evident potential adverse consequences, significant and multiple sectoral policy consequences, WW2 and cold war period .. ..
What could be learnt from the precedents?
realization of ability for global level interference; listening to science; precautionary approach; understanding of mutual international interdependence (E-W; N-S); modalities of international pol. negotiations
BUT: complexity of the problem and the policy conflicts turned to be unprecedented ..
2. UNCERTAINTIES ? w hat we know already with adequate level of certainty to act ?
Emission , concentration of greenhouse gases : evidence
CO2 : man-made emissions contribute to incr. concentrations other greenhouse gases ( CH4, N2O etc. )
A tmospheric R esidence /life- T ime ; Glob a l Wa rming P otential ART: CO2 ~100ys CH 4 _12ys N 2 O_114ys .. SF 6 _3200ys! GWP: CO 2 _1 CH 4 _25 N 2 O_298 .. CFC11_4750 SF 6 _22800
emissions 1970-2004: +70%
deforestation ~25% of ghg-em. + lessening C- sink capacities
C oncentrations from preind (1750) by 2010 (CDIAC): 280 -> 389ppm CO2 : +39% CH4: +159% N2O +20%
Global climate: causes of recent changes - very likely
complex system: atmo/hydro-/cryo-/lito-/bio-..
past: long-term changes , variability ( composition, cl.param - s ) Medieval Warm Period, Little Ice Age ..
since pre-industrial period > 0.7 C warming
Attribution (IPCC) : " Most of the .. increase in globally-averaged temperatures since the mid-20th century is very likely due to the .. increase in anth ropogenic ghg concentrations "
Obs-ed i mpacts on reg . climates , env . , soc-econ systems
climate system modeling - assessments 1990-2100 (IPCC, 2007) global aver. surface temp. rise: 1,8 - 4,0C (sea: + 18-59 cm ) huge spatial differences ..
scaling the levels of hazard - if temp increases 1-2-3-4-5C impacts on water, ecosystem, food, coasts, health if 2C < terrestrial biosph. tends toward net C-source tendencies for cereal prod. to decrease in low lat-s
change in the state of the system ..
impacts: loss of ice sheets on polar land >> metres of sea-level rise etc.
Decision-making under uncertainties
precaution : " take precautionary measures to anticipate, prevent or minimize the causes of climate change and mitigate its adverse effects. Where there are threats of serious or irreversible damage, lack of full scientific certainty should not be used as a reason for postponing such measures "
set thresholds: < 2C CO2eq < 450 ppm (445-490ppm 2.0-2.4C) emission s: peaking by 2015 and red. by at least 50 % by 2050
emission red. pathway .. 2C
3. CONCERN ? why this problem " bothers " even the high-level policymakers ?
Sources: sectors/activities of man-made emissions
energy production/cons. CO 2 ; transport CO 2 ; agriculture ( plant cultiv. CO 2 , N 2 O , animal husb. CH 4 ); manufacturing ind-s CO 2 ; other ind-s HFCs, PFC, SF6
s inks/reservoirs capacities' decrease forest management, land use (change)
Impacts : sectors/activities influenced by env. chang e
water management, agriculture, forestry, energy management, health and healthcare; nat.systems
these are key sectors of soc-econ development: significant changes are (would be) required .. = at stake e.g.: global energy or food supply future of the societies; its national and internat'l aspects
(-) pos.impacts; neglecting the hazard, other reasons ..
share of sectors in glob ghg-emissions sectors bearing the c.c. impacts
4. RE PARATION ? we have interfered with the global env/climate system: how to heal it?
Natural carbon cycle and human interference
natural carbon cycle: dyn . equilibrium for quite a long time period
man-made CO2 emissions : small compared to nat. sources (3-4%)
man-made reduction of CO2 sink capacities : small compared to ..
but these were leading to an imbalance , atm. accum . of CO2/ghg-s
Gradual refinement of "todo's" i.e. options:
1972 UNCHE: be mindful of activities in which there is an appre - ciable risk of effects on climate ; monitor long-term global trends in atm. constituents and properties which may cause ..climatic changes
1987 WCED: formulate and agree upon management policies for all env iron- ly reactive chemicals released into the atmo . by human activities, particularly those that can influence the radiation balance
1988 Toronto: dev elope d countries ' gov - s pledged: vol-ly cut CO2 emissions by 20% by the year 2005
1990 IPCC, WCC2 -d e cl aration : dev elope d c ountrie s limit emissions ..
1992 UNFCCC: Dev elope d countries: taking the lead in modifying longer-term trends in anthropogenic emissions .. and as 1st step: stabilize emissions by 2000 at 1990 level
Global carbon cycle (IPCC, 2007, Fig. 7.3.) Toronto, 1988:
RE PARATION ? options to stabilize atmospheric ghg concentrations (at a level ..)
reduce CO2 emissions from fossil fuel combustion (all sector s)
energy (supply and demand side): saving, effic . ( conver t, use ),chp,"clean-coal",coal-to-gas ..
transp ort (terr it .planning; modal shift, less fuel; fuel eff. ) , agric ulture , indust ry etc.
reduce CO2 em. by switch ing to non-fossil fuels for energy:
renewables (?) , nuke (?) ; hydrogen (?)
collect CO2 (post comb ., from atm. ) and dispose or convert
carbon capture and storage (CCS)
CO2 to methanol (?)
enhance CO2 sink capacities:
save forests (red. em-s from deforestation , degrad. , REDD)
reforest, a f forest .. ; harvested wood products ..
reduce other GHG emissions from sectoral activities:
5. ADAPTATION ? mitigation and/or adaptation ? - case of natural env variability
Vulnerability & ad aptation to natural climatic variability
vulnerability of natural systems and human soc-s to varying env . conditions - to diff erent extent
resilience depend s on adapt ation ability, capacity (early perception, preparedness, means, flexibility etc.)
West-Europe: the Little Ice Age
after a warm period prolonged cold centuries (14)16-19 c-s 1-2C below average, large interannual/-seasonal variability
impacts: agric. - shorter veget . seasons; fishing, settlements some adaptation since limited options .. ( changes in plant cultivation, abandon ing settlements ..)
Africa: the Sahel belt and the famine of 1970s
long-term adaptation to general severe conditions: traditional cattle pastoralism and migration ~ key to lower vulnerability
unusual good conditions 1950s-60s and rapid adaptation: fast agric. development ( mal adaptation), pastoralism marginalized
abrupt switch to usual dryness from late 1960s: starvation ~200 tho usands of people, millions of animals were dead ..
Mitigation i n case of natural env/clim. variability
only for the human factors exacerbating vulnerability to natural env. variability
Little Ice Age : 14 /16 -19 centuries , Northern -H, W-Europe (Mann, 2002) Sahel: annual rainfall, 1900- 2007 1968-74 and recurring dr. periods 1400 1600 1800 1200
ADAPTATION ? mitigation and/or adaptation ? - case of man-made env. change
Mitigation in case of man-made env/clim. change
both for the human factors causing and/or exacerbating the changes in env. conditions and the vulnerability to the changes
Limits in adaptability: extent and rate of the change
Ecosys : Approximately 20-30% of plant and animal species assessed so far are likely to be at increased risk of extinction if increases in global average temperature exceed 1.5-2.5ºC
Agric.: Adaptations such as altered cultivars and planting times allow low- and mid- to high-latitude cereal yields to be maintained at or above baseline yields for modest warming
IPCC : Even the most stringent mitigation efforts cannot avoid further impacts of climate change in the next few decades, which makes adaptation essential .. . Unmitigated climate change would, in the long term, be likely to exceed the capacity of natural, managed and human systems to adapt . (AR4, WGII)
UNFCCC : The ultimate objective is to achieve stabilization of ghg concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system . Such a level should be achieved within a time frame sufficient to allow ecosystems to adapt naturally to climate change .. and to enable economic dev . to proceed in a sustainable manner .
EU: adaptation policy (COM: White Paper, 2009) Addressing c . c . requires two types of response. Firstly, and importantly, we must reduce our gh g emissions and secondly we must take adap - tation action to deal with the unavoidable impacts . C limate change, Hungary mitigating the hazard . pre - paring for impacts (2003-8) O bjective of the Project : systemization of the scientific results on the c . c . hazard, assessment of its impacts , the science-based national mitigation and adaptation response policy options . NAPA: Maldives .. to present a coherent frame -__ work to c . c . adaptation that enhances the resilience of the natural, human, and social systems and ensures their sustainability in the face of predicted climate hazards
6. RESPONSIBILITY ? - common but differentiated responsibility and how to quantify it ?
Who is responsible: extent, indicator?
present emissions (ghg-s + lucf): huge diff-s *traditional distinction between I Cs and DCs *diff-s within groups (ICs: EiTs / DCs: emerg, LDCs)
"accumulative" type problem vs today's emissions: grad. changing contributions
responsibility at various stages of interference: ultimately, the share in resp. for adverse impacts
responsibility at diff. levels of "emitters": groups of countries, countries, companies, individuals
present-future: intra- & intergenerational equity
past and future C-based dev and em-s: I Cs and DCs
accepted in principle (FCCC): largest share of hist . glob emissions has originated in IC s - should take the lead
At which stage of interference?
emissions? + concentration s ? +GWP? + temperature?
responsibility for adverse global impacts ?
P er capita responsibility : present (and future ?)
Carbon-footprint for each individual vs glb=3.8 tCO2
GHGs+lucf 2000 (WRI) tCO2eqL: MY 37 AUS 26 CAN 24 USA 23 RF 14 DE 12 UK 11 HU 7 CN 4 IN 2 vs glb=6.8
CO2-emissions tCO2/cap, 2002 (UNEP-GRID, 2005) US 20 S-Arabia, AUS 18 CAN 14 RF 10 UK, DE 10 S-Afr 7.5 CN 2 IN 1 Togo 0.5 Malaysia 6 1960-2005 US CN CN US
7. CONVERGENCE ? i nternational sci . and pol . developments: convergence or divergence ?
Past: side-by-side sci and pol developments
1988 establ of IPCC - spec mandate, spec. structure 1988 Toronto meeting and UNGA resolution
1990 WCC2; IPCC AR1: " Emissions resulting from human activities are substantially increasing the atm . conc entration s of ghg - s .. " 1990 UNGA, 1991 nego-s, 1992 UNFCCC stabilize (ICs)
1997 AR2: " The balance of evidence suggests a discernible human influence on global climate .. " 1997 Kyoto Protocol - reduce (ICs)
2001 AR3: " An increasing body of observations gives a collective picture of a warming world and other changes in the climate system " 2001 Marrakech Accords - completing the KP ..
2007 AR4: " Continued ghg emissions at or above current rates would cause further warming and induce many changes in the glob climate system during the 21st century " 2007 Bali Mandate for further nego-s - to agree by 2009 ..
Future ? more evidence, pol icy options but more diff to agree
2010 : CO2 389 ppm +39% and other obs, but 2014 : AR5