Showing posts with label klimatske promene. Show all posts
Showing posts with label klimatske promene. Show all posts

Tuesday, September 2, 2014

THE IMPACTS OF CLIMATE CHANGES ON THE RISK OF NATURAL DISASTERS

In recent years, serious decisions are made at the local and international level on climate change and its impact on natural disasters, which are more numerous and more serious over the years. Exploring their mutual influences, scientists worldwide are mostly engaged in the issue of the link between the increase in average temperature of the earth and the frequency (intensity) of natural disasters, with a special emphasis on hydrologic and meteorological disasters. To be able to analyze such influence, it is needed a solid knowledge of climate changes and natural disasters, as it is well known that global warming does not affect equally all kinds of those disasters, taking into account the origin of their occurrence. However, it should be noted that natural disasters have always existed, and that climate changes can only affect the increase in their number, intensity and consequences that they cause to people and their material goods.
             Without going into multiply multidimensional various issues of climate change, it should be noted that climate changes are caused by emissions of different gases that directly or indirectly exacerbate the natural process by which infrared radiation is captured in the atmosphere, which causes heating the lithosphere, hydrosphere and atmosphere. It is a fact that speaks of the temperature increase of land, sea and air causes the disorder of certain natural processes, thereby contributing to the creation of more frequent floods, hurricanes, landslides and so on. Therefore, global warming that is characterized by increasing average temperatures on earth can be direct/indirect cause of the increase in severity (number and intensity) of natural disasters. In order to examine this possibility, it is important to examine the effects of elevated temperatures of land, sea and air on the processes that contribute to the above-mentioned increase in severity of natural disasters. Besides the increase in the average temperature of the lithosphere, hydrosphere and atmosphere, which are direct consequences of climate changes, it is important to analyze its indirect effects as well, such as increasing the level of the oceans and seas affected by the rapid melting of large glaciers in Antarctica and Greenland. The aforementioned process also affects the natural disasters, but in different ways than the direct effects of climate change.
      A large number of research studies worldwide have identified and demonstrated the interconnectedness of global warming and natural disasters using different statistical models. For example, if we start from the fact that the strength of hurricanes is based on heat of the oceans and seas, which is later transformed in mechanical strength, it is easy to examine the relationship between changes in ocean temperature and hurricane strength over the past few years. Of course, it is necessary to bear in mind that the characteristics of a hurricane do not only depend on the water temperature, but also on other factors that we will not consider in the paper.
            Therefore, this paper will analyze the phenomenological structure of climate changes and natural disasters, for further consideration of the relevant facts about their interrelation. Namely, in order to link those two phenomena it should consider each separately. Therefore, the paper will consider the implications of climate changes on natural disasters with special reference to their impact on specific species, the intensity and the increase in their number.
The climate changes

Across the Earth, climate changes and its serious consequences are discussed on a daily basis. And what exactly are climate changes and what they represent, it is best explained by the process of warming the Earth. Namely, daily solar energy penetrates the atmosphere in the form of light waves. Part of this energy heats the Earth, and part in the form of infrared waves back into space. Normally, part of the infrared radiation usually is captured by the atmosphere allowing the temperature that stays on Earth is within acceptable limits. However, the problem we now face is that the thin layer of air layer became thicker due to the large amounts of carbon dioxide and other gases that cause the greenhouse effect. Having become thicker, now that layer retains a large amount of infrared radiation that would otherwise have left the atmosphere, causing the temperature of the Earth's atmosphere and oceans begin to rise.According to the U.S. Environmental Protection Agency – EPA, climate changes are a significant changes in climatic conditions, such as temperature, precipitation or winds, which last for a decade or longer, and may result from: natural processes within the climate system (changes in ocean circulation), changes in the intensity of solar radiation, or human activities that affect the composition of the atmosphere (through the burning of fossil fuels) and the land surface (deforestation, urbanization, desertification).[1] In addition, unlike climate changes, term the „global warming“ represents the tropospheric temperature increase thus contributing to changes in global weather patterns that emerge due to increased emissions of so-called greenhouse gases, mainly carbon dioxide and methane.[2
Climate changes represent a serious threat to the basic elements of life for people in the world, such as access to drinking water, food production, food and land use. They are multiple (from drought to floods) and multidimensional (local to global) risks that have short, medium and long-term aspects and unknown outcomes. The signatories to the UN Convention on Climate Change and the Kyoto Protocol 1997 have accepted that climate changes carry many potential hazards, such as sea level rise, increased frequency of storms and floods, the spread of infectious diseases, decline in biodiversity and reducing the availability of food and water. These impacts are a threat to human life and sustainable development.

Za citiranje koristiti: Cvetković, V. (2014). The impacts of climate changes on the risk of natural disasters. Skopje: International yearbook of the Faculty of security (51-60).



[1] Dimitrijević, D.: Trendovi ekološke bezbednosti u XXI veku. Univerzitet u Beogradu: Fakultet bezbednosti, 2010. godine.
[2] Environmental Protection Agency, U.S. Enviromental Protection Agency: Nanotechnology White Paper, Washington, 2007.

Sunday, August 11, 2013

UTICAJI KLIMATSKIH PROMENA NA RIZIK OD PRIRODNIH KATASTROFA

Klimatske promene koje predstavljaju povećanje prosečnih temperatura u atmosferi, hidrosferi i litosferi na različite načine utiču na povećanje frekventnosti i inteziteta prirodnih katastrofa. Globalno zagrevanje posebno utiče na hidrološko-meteorološke katastrofe jer su one u najtesnijoj vezi sa posledicama klimatskih promena.





Слика бр. 1.: Могуће последице утицаја климатских промена (Преузето са http:///www.Google. news )

Dakle, opšti porast temperature dovodi do porasta broja toplih dana, smanjenju broja hladnih dana, u svim oblastima na zemlji.[1] U srednjim i višim delovima severne polulopte, zapažanja ukazuju na povećanje padavina, koje doprinose nastanku različitih vrsta poplava i nastajanju klizišta i erozija zemljišta. U nekim delovima, kao što su Afrika i Azija, učestalost i intenzitet suša se povećao tokom poslednjih nekoliko decenija. Takve promene su u skladu sa intenziviranjem hidrološkog sistema.[2] Od 1900 do 2005. godine padavine su se značajno povećale u istočnim delovima Severne i Južne Amerike, severne Evrope i severne i centralne Azije, a smanjile su se u Sahelu, na Mediteranu, u južnoj Africi i delovima južne Azije. Na globalnom nivo, oblast pogođena sušom verovatno se povećala od 1970 – ih. Vrlo je verovatno da su tokom poslednjih 50 godina hladni dani, hladne noći i mrazevi ređi u većini kopnenih oblasti, a da su vreli dani i vrele noći češće. Takođe, verovatno je da su toplotni talasi češći u većini kopnenenih oblasti, da se u većini oblasti povećala učestalost velikih padavina i da je od 1975. godine u celom svetu povećana učestalost ekstremnog povećanja nivoa mora. Postoje i dokazi na osnovu posmatranja o povećanju inteziteta aktivnosti tropskih ciklona na Severnom Atlantiku otprilike od 1970. godine sa ograničenim dokazima o povećanju na drugim mestima. Promene u snegu, ledu i smrznutom tlu sa velikom pouzdanošću su uticale na povećanje broja i veličine glečerskih jezera, povećanje nestabilnosti zemljišta u planinama i drugim regionaima izazivajući mnogobrojna klizišta i poplave. Predviđanja za naredni vek pokazuju da će broj toplih i veoma tolih dana nastaviti da raste, a da će broj hladnih i veoma hladnih dana opasti u gotovo svim regionima sveta. [3]Pored toga, intenzitet i učestalost ekstremnih padavina će se vrlo verovatno povećati u mnogim oblastima, što će usloviti brojne polave i klizišta. Srednje kontinentalne oblasti će uglavnom biti sušnije, što će povećati rizik od letnjih suša i požara. Tabela 1, data na sledećoj strani pokazuje pregled ovakvih uticaja.  Dok su promene ekstremnih temperatura prilično očekivane, a u mnogim oblastima promene u učestalosti padavina ili suša mogu biti predviđene sa velikom pouzdanošću, neke male atmosferske promene podležu većoj neizvesnosti. Nema pouzdanih predviđanja za manje fenomene, uključujući oluje, tornada, oluje sa gradom, munje i gromove.[4]
Već je konstatovano da globalno zagrevanje podiže temperaturu okeana i mora, što dalje prouzrokuje sledeće promene: toplija voda povećava količinu vlage u uraganu, kao što i topliji vazduh sadrži više vlage.[5] Kada se steknu odgovarajući uslovi, najveći deo te vlage oslobađa se u obliku velikih jednokratnih kiša ili snežnih padavina, prouzrokovajući poplave i snežne oluje. Delimićno usled toga, broj velikih poplava se na svim kontinetnima povećava iz decenije u deceniju.
U mnogim delovima sveta, globalno zagrevanje povećava i procenat godišnjih padavina u vidu kiša, a ne snega, što dovodi do velikih poplava u proleće i početkom leta. Godina 2005. u Evropi je bila obeležena neuobičajenim prirodnim katastrofama. Iste godine u SAD se dogodila serija snažnih uragana bez presedana. Novinska agencija UPI je 2005. godine rezimirala osećanja mnogih evropljana kada je izvestila da je: ,,Priroda u Evropi poludela“. Poplave u Aziji su takođe bile učestalije. U Mumbaju (Indija) visina vodenog taloga je dostigla 94 cm, za 24 časa. Bila je to neosporno najveća količina padavina koja je ikada zabeležena u jednom indijskom gradu. Rekordne poplave su zabeležene i u Kini, koja kao jedna od najstarijih civilizacija poseduje najbolju evidenciju o poplavama od bilo koje zemlje na svetu. Sa druge strane, paradoksalno je to što globalno zagrevanje izaziva ne samo češće poplave, već i češće suše.
Globalno zagrevanje s jedne strane dovodi do toga da iz okeana isparava sve više vode koja se taloži u atmosferi kao topla para, a sa druge strane više vlage izvlači iz zemlje. Delimično usled toga, pustinje se u celom svetu iz decenije u decenije sve više šire. Jedan od razloga za ovaj paradoks jeste činjenica da globalno zagrevanje ne povećava samo količinu padavina izazivajući velike poplave u celom svetu, već ih delimično i preusmerava. Statističke analize su pokazale da je količina padavina u svetu u proteklih 10 godina, porasla za 20%. Međutim, uticaj klimatskih promena na količinu padavina nije svuda isti. Padavine su se u nekim regionima povećale a u nekim smanjile.



Figure 4: World temperature and natural disasters in LDCs, 1960-2005[6]

Prikazani grafikon pokazuje trend porasta prosečnih temperatura i broja prirodnih katastrofa od 1960. do 2005. godine. Na osnovu njega nedvosmisleno se može uvideti da porast temperature prati i porast prirodnih katastrofa. Naravno, imajući u vidu da su prirodne katastrofe rezultat kombinacije prirodnih procesa i njihovih posledica po ljude, jasno je da narušavanje prirodnog procesa koje se ogleda u temperaturnim promenama utiče i na prirodne katastrofe koje su deo tog istog procesa u prirodi. Protekle decenije, katastrofe koje su bile povezane sa vremenskim prilikama su bile uzrok čak 90% prirodnih katastrofa, 60 % smrtih slučajeva i bile odgovorne za 98% slučajeva za opadanje kvaliteta života stanovništva naseljenog u toj oblasti.[7]  Svetska meterološka organizacija izvestila je u decembru 2005. godine  da će ta godina ostati upamćena po desetinama zapisa prirodnih katastrofa, od suše u Brazilu, hladnoće u Pakistanu, do uragana na Atlanskom okeanu. Osim 1996. godine, prethodnih 10 godina su bile u rangu 10 najtoplijih od 1850.
Manje od mesec dana pre nego što je uragan Katrina pogodio SAD, 2005. godine, jedno obimno istraživanje urađeno na Masačusetskom institutu za tehnologiju (Massachusets Institute of Technology) potrvrdilo je naučni konsenzus da globalno zagrevanje čini uragane jačim i razornijim. Veliki uragani koji nastaju u Atlanskom i Tihom okeanu, od sedamdesetih godina prošlog veka za oko 50% su jači i dugotrajniji nego pre toga.[8]





[1] Smith, L.: Statistical Trend Analysis in Weather and Climate Extremes in a Changing Climate. Regions of Focus: North
America, Hawaii, Caribbean, and U.S. Pacific Islands. T.R. Karl, G.A. Meehl, C.D. Miller, S.J. Hassol, A.M. Waple, and W.L. Murray
(eds.). A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research, Washington, DC., 2008.
[2] Isto.
[3] Lynch, A., Uotila, P., Cassano, J.: Changes in synoptic weather patterns in the polar regions in the 20th and 21st centuries, Part 2: Antarctic. International Journal of Climate, 26(9), 1181-1199, 2009.
[4] Yoshimura, J., Sugi, M., Noda, A.: Influence of greenhouse warming on tropical cyclone frequency. Journal of the Meteorological Society of Japan, 84(3), 405-428, 2006.
[5] Al Gor.: Neprijatna istina, planetarna opasnost od globalnog zagrevanja i šta u vezi sa tim možemo da učinimo. London: Wylie Agency, 2008.
[6] Source: Goddard Institute for Space Studies (GISS), NASA GISS Surface Temperature Analysis (GISTEMP) (http://data.giss.nasa.gov/gistemp/); and UNCTAD secretariat estimates, based on EM-DAT: The OFDA/CRED International Disaster database (www.emdat.net), Université catholique de Louvain, Louvain-La-Neuve.
[7] Yonetani, T., Gordon, H.: Simulated changes in the frequency of extremes and regional features of seasonal/annual temperature and precipitation when atmospheric CO2 is doubled. Journal of Climate, 14(8), 1765-1779, 2001.
[8] Studija MIT-a, 2005.

Videti opširnije: Cvetković, V. (2013). Uticaji klimatskih promena na rizik od prirodnih katastrofa. U proceduri objavljivanja. Cvetković, V. (2013). Klimatske promene i nacionalna odbrana. U proceduri objavljivanja.