Main contributing factors to changes of Earth´s climate

- change of Earth’s orbit- greenhouse effect- thermal pollution- chemical pollution- (de)forestation- volcanic activities- change of Earth’s magnetism- other

History of greenhouse effectHistory of greenhouse effect

1827. Jean B. J. Fourier:1827. Jean B. J. Fourier: «Light find less resistance in penetrating the air, than in repassing «Light find less resistance in penetrating the air, than in repassing into the air when converted to heat.» into the air when converted to heat.»

1860. John Tyndall:1860. John Tyndall: showed that COshowed that CO22 and water vapor both absorb and emit infrared and water vapor both absorb and emit infrared

radiation.radiation.

1896. Svante Arrhenius:1896. Svante Arrhenius: showed by calculation in a simplified model that a 50% increase of showed by calculation in a simplified model that a 50% increase of COCO22 would warm the Earth´s surface by 3 would warm the Earth´s surface by 3 ooC.C.

1914.-1938. Milutin Milanković:1914.-1938. Milutin Milanković:showed by calculation that a quasiperiodic change of Earth´s orbit showed by calculation that a quasiperiodic change of Earth´s orbit around Sun causes the interchange of global warming and global around Sun causes the interchange of global warming and global cooling.cooling.

1938. Stewart Callender:1938. Stewart Callender:in a simple model predicted that projected increase of in a simple model predicted that projected increase of atmospheric COatmospheric CO22 would increase the temperature by about 0.3 would increase the temperature by about 0.3 ooC C

per century.per century.

1960.-1980. actual global cooling:1960.-1980. actual global cooling:provided a scientific argument against attribution of early 20th provided a scientific argument against attribution of early 20th century warming to COcentury warming to CO22 increase. increase.

1982. US NAS1982. US NAScomputed based prediction that doubling of COcomputed based prediction that doubling of CO22 atmospheric atmospheric

concentration would lead to increase of temperature of 1.5-4.5 concentration would lead to increase of temperature of 1.5-4.5 ooC.C.

2007. IPCC 20072007. IPCC 2007computed based prediction increase of COcomputed based prediction increase of CO22 atmospheric atmospheric

concentration in 21st century would lead to increase of concentration in 21st century would lead to increase of temperature of 1.1-6.4 temperature of 1.1-6.4 ooC.C.

COCO22 concentration in atmosphere concentration in atmosphere

before 35 before 35 000 000 000 000 years years 2,000 ppm2,000 ppmbefore 20 before 20 000000 year years s 200 ppm200 ppm1807.1807. 280 ppm280 ppm1858.1858. 288 ppm288 ppm1914.1914. 300 ppm300 ppm1950.1950. 310 ppm310 ppm1970.1970. 325 ppm325 ppm1985.1985. 345 ppm345 ppm20072007.. 380 ppm380 ppm

GREENHOUSE GASESGREENHOUSE GASES

COCO22

CHCH44

FClCH FClCH OO33

NN22O O

OtherOther

OCEANS – ATMOSPHERIC COOCEANS – ATMOSPHERIC CO22 SINK SINK

Volcanoes bring COVolcanoes bring CO22 and volcanic rocks from deep and volcanic rocks from deep

inside the Earth to the surface.inside the Earth to the surface.

Rainfall picks up some CORainfall picks up some CO22 from the atmosphere from the atmosphere

making a weak acid. That acid breaks rocks down making a weak acid. That acid breaks rocks down and particles of rock and COand particles of rock and CO22 are washed to the are washed to the

ocean.ocean.

Chemical reaction stores COChemical reaction stores CO22: :

rock (CaSiOrock (CaSiO33) + CO) + CO22

sediments at ocean floor (CaCOsediments at ocean floor (CaCO33 + SiO + SiO22))

The rate at which COThe rate at which CO22 is removed from the atmosphere is removed from the atmosphere

increases with increasing temperature. Therefore, increases with increasing temperature. Therefore, greenhouse effect acts as thermostat. greenhouse effect acts as thermostat.

During the last 8,000 years human activity was During the last 8,000 years human activity was introducing additional COintroducing additional CO22 into atmosphere. into atmosphere.

Ocean absorbs 50% of yearly COOcean absorbs 50% of yearly CO22 production. production.

Lifetime of atmospheric COLifetime of atmospheric CO22 is about 100 years (before is about 100 years (before

being absorbed by oceans, soil and biosphere)!being absorbed by oceans, soil and biosphere)!

COCO22 Cycle: Cycle:

volcanoes atmosphere ocean sediments volcanoes atmosphere ocean sediments Earth´s interior volcanoes .....Earth´s interior volcanoes .....

«JUMPING» CLIMATE«JUMPING» CLIMATECLIMATE OVER THE PAST 100,000 YEARSCLIMATE OVER THE PAST 100,000 YEARS

Over the past 100,000 years there were only two vaguely Over the past 100,000 years there were only two vaguely stable periods of climate:stable periods of climate: - - the first was when the ice age was coldest, about the first was when the ice age was coldest, about 20,000 years ago, during period of a few thousand 20,000 years ago, during period of a few thousand

years, andyears, and - - the second is the recent period over the last 10,000 the second is the recent period over the last 10,000 years.years.

But for the most of the last 100,000 years, a «jumping» But for the most of the last 100,000 years, a «jumping» climate has been the rule, not the exception. Slow climate has been the rule, not the exception. Slow cooling has been followed by abrupt cooling, centuries cooling has been followed by abrupt cooling, centuries old, and then abrupt warming, with the abrupt warming old, and then abrupt warming, with the abrupt warming generally about 1,500 years apart, although with much generally about 1,500 years apart, although with much variability.variability.

At the abrupt jumps, the climate often flickered At the abrupt jumps, the climate often flickered between warm and cold for a few years at the between warm and cold for a few years at the time before settling down. time before settling down.

The best known abrupt climate change, the The best known abrupt climate change, the Younger Dryas event 11,500 years ago, when Younger Dryas event 11,500 years ago, when Greenland warmed about 8 Greenland warmed about 8 ooC in a decade.C in a decade. The history of this climatic «craziness» is The history of this climatic «craziness» is written down in the ice of Greenland and written down in the ice of Greenland and Antarctic, in cave formations, ocean and lake Antarctic, in cave formations, ocean and lake sediments and other places. This million-year sediments and other places. This million-year archive provides year-by-year records of air and archive provides year-by-year records of air and water temperature, ice sheets, storms, oceans water temperature, ice sheets, storms, oceans etc.etc.

The current stable climate interval is The current stable climate interval is among the longest in the record of global among the longest in the record of global

climate! climate! Nature is thus likely to end our friendly Nature is thus likely to end our friendly

climate, perhaps quite soon.climate, perhaps quite soon.In such a situation one should be careful In such a situation one should be careful

not to provoke it!not to provoke it!

EARTH IS A SENSITIVEEARTH IS A SENSITIVE DYNAMIC «BEING», DYNAMIC «BEING»,

UNDERGOINGUNDERGOING C CONTINUOUS ONTINUOUS CHANGES!CHANGES!

CONCLUSIONS:CONCLUSIONS:

1.Climate in the past has been wildly variable, 1.Climate in the past has been wildly variable, with larger and faster changes than anything with larger and faster changes than anything humans have ever faced during last five humans have ever faced during last five thousand yearsthousand years

2. Climate can be rather stable during some 2. Climate can be rather stable during some times, but when the climate is «pushed» or times, but when the climate is «pushed» or forced to change, it often jumps suddenly to forced to change, it often jumps suddenly to very different conditions. very different conditions.

3. Small «pushes» have caused large changes 3. Small «pushes» have caused large changes because many processes in the Earth´s system because many processes in the Earth´s system amplify the pushesamplify the pushes

(similar to sensitive dependence of (similar to sensitive dependence of deterministic chaos for nonlinear systems).deterministic chaos for nonlinear systems).Greenhouse gases have probably been Greenhouse gases have probably been important amplifiers.important amplifiers.The great ice sheets that grew to cover much of The great ice sheets that grew to cover much of Europe and North America only 20,000 years Europe and North America only 20,000 years ago were responding to changes in the Earth´s ago were responding to changes in the Earth´s planetary orbit.planetary orbit.

4. There is remarkable evidence for «jumping» 4. There is remarkable evidence for «jumping» climates, which have been especially prominent climates, which have been especially prominent during coolings and warmings of the orbitally during coolings and warmings of the orbitally driven ice ages.driven ice ages.AND SUCH SITUATION IS ABOUT NOW!AND SUCH SITUATION IS ABOUT NOW!

IPCC IPCC (Intergovernmental Panel on Climate (Intergovernmental Panel on Climate Change)Change)

Previous IPCC predictions: Previous IPCC predictions: from 1990. onwards global temperature from 1990. onwards global temperature would rise by between 0.15 would rise by between 0.15 ooC and 0.3 C and 0.3 ooC C per decade.per decade.

The actual increase after 1990.The actual increase after 1990.:: 0.2 0.2 00C per decadeC per decadefits the initial prediction.fits the initial prediction.

IPCC Report (2007)IPCC Report (2007)::WWith over 90% probability («very likely») recent ith over 90% probability («very likely») recent temperature increases are driven by human temperature increases are driven by human activities.activities.

EEstimate of COstimate of CO22-doubling response:-doubling response:

2.0-4.5 2.0-4.5 ooC mean temperature riseC mean temperature rise resulting from resulting from doubling of COdoubling of CO22 level. level.

Prediction for temperature increase Prediction for temperature increase in 21in 21st st centurycentury::1.1-6.4 1.1-6.4 ooC.C.

Predictions of rise of sea level Predictions of rise of sea level in 21in 21st st centurycentury : :between 19 cm and 58 cm.between 19 cm and 58 cm.

HOW REALISTIC ARE MATHEMATICALHOW REALISTIC ARE MATHEMATICAL MODELS OF GLOBAL CLIMATE?MODELS OF GLOBAL CLIMATE?

To predict future climate it is necessary to develop mathematical To predict future climate it is necessary to develop mathematical model of physical processes in the coupled system of atmosphere, model of physical processes in the coupled system of atmosphere, oceans, ice sheets, biosphere, human activities etc. oceans, ice sheets, biosphere, human activities etc.

Because of extreme complexity, only very simplified models are Because of extreme complexity, only very simplified models are available what seriously limits the reliability of model predictions. available what seriously limits the reliability of model predictions. This was shown many times by inability of climatic models to This was shown many times by inability of climatic models to predict many known climatic changes from the past, starting the predict many known climatic changes from the past, starting the model earlier in the past and seeing whether the model can model earlier in the past and seeing whether the model can «predict» the things that we know have happened.«predict» the things that we know have happened.

Therefore, science can not give fully reliable prediction for future Therefore, science can not give fully reliable prediction for future climate, but only more or less probable outcomes (it is even climate, but only more or less probable outcomes (it is even uncertain how large is the probability).uncertain how large is the probability).

MMuch more research is needed!uch more research is needed!

NATURE (2007) What we don´t know NATURE (2007) What we don´t know about climate changeabout climate change

Report from IPCC (Intergovernmental Panel on Climate Report from IPCC (Intergovernmental Panel on Climate Change) (2007) has a finely calibrate lexicon of Change) (2007) has a finely calibrate lexicon of certainty: «virtually certain», «very likely», «more likely certainty: «virtually certain», «very likely», «more likely than not» when assigning the probability of climate than not» when assigning the probability of climate effects of human activities. Some conclusions remain effects of human activities. Some conclusions remain more uncertain than the others.more uncertain than the others.

Perhaps most critically, researchers know relatively Perhaps most critically, researchers know relatively little feedback effects that might enhance- or weaken – little feedback effects that might enhance- or weaken – the pace and effects of climate change. The complex the pace and effects of climate change. The complex flow of carbon between soils, plants, the oceans and flow of carbon between soils, plants, the oceans and the atmosphere is still being investigated.the atmosphere is still being investigated.

Key sticking points include the inability of global Key sticking points include the inability of global climate models to produce the amount of sea-level climate models to produce the amount of sea-level rise observed over the past couple of decades.rise observed over the past couple of decades.

IPCC Report gives first forecasts how changing IPCC Report gives first forecasts how changing climate might affect particular regions of the world, climate might affect particular regions of the world, but improved analyses that incorporate clouds, snow but improved analyses that incorporate clouds, snow and ice must be developed.and ice must be developed.

Extreme weather is another example of the Extreme weather is another example of the remaining uncertainties.remaining uncertainties.

Improving the models requires better data. Gaps and Improving the models requires better data. Gaps and errors in observation are attributable to many errors in observation are attributable to many causes. causes.

Caution is necessary in interpreting the IPPC data!Caution is necessary in interpreting the IPPC data!

NATURE 419(2002) K.Lambeck et al. Links between climate and NATURE 419(2002) K.Lambeck et al. Links between climate and sea levels for the past three million yearssea levels for the past three million years The major sea-level cycles occur at intervals of about 100,000 The major sea-level cycles occur at intervals of about 100,000 years over the past about 800,000 years, with maximum years over the past about 800,000 years, with maximum amplitude of 120-140 m.amplitude of 120-140 m.

NATURE 445 (2007) G.J. Bowen, When the world turned coldNATURE 445 (2007) G.J. Bowen, When the world turned coldBefore 34 million years, Antarctica has been a lush, green Before 34 million years, Antarctica has been a lush, green continent for several tens of millions of years.continent for several tens of millions of years.Then, in a period of 300.000 years temperature dropped by about Then, in a period of 300.000 years temperature dropped by about 8 8 ooC and COC and CO22 concentration dropped several times from its initial concentration dropped several times from its initial

value of about 2,000 ppm to about few hundred ppm. Ice sheets value of about 2,000 ppm to about few hundred ppm. Ice sheets grew over most of Antarctica.grew over most of Antarctica.

NATURE, 446 (2007). S. Bain et al. Effect of natural iron NATURE, 446 (2007). S. Bain et al. Effect of natural iron fertilization on carbon sequestration in the Southern Oceanfertilization on carbon sequestration in the Southern OceanIron concentration in surface waters plays important role on the Iron concentration in surface waters plays important role on the uptake of carbon in oceans and may have more significant effect uptake of carbon in oceans and may have more significant effect on atmospheric COon atmospheric CO22 concentration than previously thought. concentration than previously thought.

NATURE, 446 (2007) Q. Shiermeier, The new face of ArcticNATURE, 446 (2007) Q. Shiermeier, The new face of ArcticHow the Arctic might change in 2027.How the Arctic might change in 2027.- The Arctic Ocean remains ice-free in September.- The Arctic Ocean remains ice-free in September.- All known Russian offshore oil and gas deposits are - All known Russian offshore oil and gas deposits are exploited commercially.exploited commercially.- Offshore oil and gas resources unknown today are being - Offshore oil and gas resources unknown today are being extensively developed.extensively developed.- Oil tankers and container ships sail the Northeast passage.- Oil tankers and container ships sail the Northeast passage. NATURE, 426 (2003) Q. Shiermeier, Climate study highlights NATURE, 426 (2003) Q. Shiermeier, Climate study highlights inadequacy of emission cutsinadequacy of emission cutsThe Kyoto Protocol calls for average cuts of 5% by 2012.The Kyoto Protocol calls for average cuts of 5% by 2012.German Advisory Council on Global Change concludes that German Advisory Council on Global Change concludes that global COglobal CO22 emissions would need to be curbed by 45-60% by emissions would need to be curbed by 45-60% by

2050 compared with 1990 levels.2050 compared with 1990 levels.

NATURE, 448 (2007) P. Pilewskie, Aerosols heat upNATURE, 448 (2007) P. Pilewskie, Aerosols heat upSolid particles suspended in atmosphere have long played Solid particles suspended in atmosphere have long played second fiddle to greenhouse gases as agents of climate second fiddle to greenhouse gases as agents of climate change. A study of atmospheric heating over the Indian change. A study of atmospheric heating over the Indian ocean could provoke a rethink.ocean could provoke a rethink.

SCIENCE, 286 (1999) J.P. Severinghaus, Abrupt climate SCIENCE, 286 (1999) J.P. Severinghaus, Abrupt climate change at the end of last glacial periodchange at the end of last glacial periodGreenland warmed 9 Greenland warmed 9 ooC (6-12 C (6-12 ooC) abruptly over a period of C) abruptly over a period of several decades, beginning 14,672 years ago.several decades, beginning 14,672 years ago.

NATURE, 448 (2007) V. Ramanathan et al. Warming trends in NATURE, 448 (2007) V. Ramanathan et al. Warming trends in Asia amplified by brown cloud solar absorptionAsia amplified by brown cloud solar absorptionWe suggest that atmospheric brown clouds contribute as We suggest that atmospheric brown clouds contribute as much as the recent increase in anthropogenic greenhouse much as the recent increase in anthropogenic greenhouse gases to regional lower atmospheric warming trends. We gases to regional lower atmospheric warming trends. We propose that the combined warming trend of 0.25 propose that the combined warming trend of 0.25 ooC per C per decade may be sufficient to account for the observed retreat decade may be sufficient to account for the observed retreat of the Himalayan glaciers.of the Himalayan glaciers.

NATURE, 448 (2007) N. Stafford The other greenhouse effectNATURE, 448 (2007) N. Stafford The other greenhouse effectCommercial greenhouses contain 700 ppm or more of COCommercial greenhouses contain 700 ppm or more of CO2 2 ..

Rising CORising CO22 concentration increases crop yields but decreases concentration increases crop yields but decreases

nutritional quality.nutritional quality.

NATURE, 404 (2000) C.S. Hvidberg, When Greenlad ice meltsNATURE, 404 (2000) C.S. Hvidberg, When Greenlad ice melts130,000 to 110,000 years ago the climate was warmer than 130,000 to 110,000 years ago the climate was warmer than today, and the sea level was six meters higher than today.today, and the sea level was six meters higher than today.20,000 years ago the sea level was 120 meters lower than today.20,000 years ago the sea level was 120 meters lower than today.

NATURE, 448 (2007) O. Norton, Is this what it takes to save the NATURE, 448 (2007) O. Norton, Is this what it takes to save the world?world?Geoengineering can be used to cool the Earth.Geoengineering can be used to cool the Earth.Introducing one or two million tons of sulphur into the Introducing one or two million tons of sulphur into the stratosphere every year as a way to keep the protective stratosphere every year as a way to keep the protective effects.effects. Large number of sliver-like fliers could be launched from Earth Large number of sliver-like fliers could be launched from Earth and used to partially shield the Earth from Sun´s rays (to cut and used to partially shield the Earth from Sun´s rays (to cut down sunlight by about 2%).down sunlight by about 2%).

NATURE, 448 (2007) M. Hopkin, Climate panel offers ground for NATURE, 448 (2007) M. Hopkin, Climate panel offers ground for optimismoptimismIf COIf CO22 emissions were given a cost of 50 USD per tonne, economic emissions were given a cost of 50 USD per tonne, economic

forces could drive global emissions in 2030 20% to 50% lower than forces could drive global emissions in 2030 20% to 50% lower than they would otherwise have been. they would otherwise have been.

Technologies and practices that can help mitigate climate change Technologies and practices that can help mitigate climate change (sector energy)(sector energy) Currently available:Currently available: More efficient supply and distribution More efficient supply and distribution Combined heat and power Combined heat and power Renewables Renewables Nuclear Nuclear Early carbon capture and storage Early carbon capture and storage Commercially available by 2030:Commercially available by 2030:Carbon capture and storageCarbon capture and storageAdvanced nuclear powerAdvanced nuclear powerAdvanced renewablesAdvanced renewablesNew solar concentrators and cellsNew solar concentrators and cells

GOALS:GOALS:

PeoplePeople should be better educated and informed! should be better educated and informed!

Scientific and technological development should Scientific and technological development should provide more energy efficient and environmentally provide more energy efficient and environmentally friendly devices!friendly devices!

Scientific and technological development should Scientific and technological development should provide abundant and ecologically cleaner energy provide abundant and ecologically cleaner energy sources!sources!

We should change our lifestyle to spend less energy!We should change our lifestyle to spend less energy!

Getting the people ready for action, rather than Getting the people ready for action, rather than passive or depressed!passive or depressed!

Climatic Change in Croatia

5-year mean temperature in 1999.-2003. and 2004.-2008. in Croatia.Input mean annual temperature data are taken from Meteorological and hydrological service of Republic of Croatia.Fourteen climatological stations are chosen randomly from the station network in Croatia, including coastal, continental and mountain regions.

Climatological Mean temperature (°C) Temperature change (°C) station 1999.-2003. 2004.-2008. Zagreb 13.02 12.68 -0.34Osijek 11.84 11.56 -0.28Pozega 11.82 11.36 -0.46Gospic 9.86 9.58 -0.28Crikvenica 15.58 15.15 -0.43Hvar 17.16 16.82 -0.34Split 16.96 16.66 -0.30Dubrovnik 17.22 16.84 -0.38Varazdin 11.40 11.04 -0.36Daruvar 11.48 11.06 -0.42Ogulin 11.22 10.76 -0.46Pazin 12.18 11.66 -0.52Zavizan (mountain top) 4.34 3.94 -0.40 Knin 13.62 13.22 -0.40

Mean temperature change: -0.38 °C.