Uzroci promjene klime na Zemlji

Godinama stručnjaci istražuju uzroke klimatskih promjena. Prema dosadašnjim spoznajama uzroci klimatskih promjena mogu biti prirodni, ali i antropogeni. Od prirodnih uzroka ovdje su Milankovićevi ciklusi (promjena ekscentričnosti Zemljine orbite, promjena nagiba i precesije Zemljine rotacijske osi) koji djeluju u relativno pravilnim vremenskim rasponima. Intenzitet Sunčevog zračenja koji ima ciklički karakter, fenomen ENSO kojem pripadaju El Niño i La Niña, krute čestice vulkanskog pepela i šumski požari također su pribrojeni prirodnim uzrocima. Antropogeni uzroci pretežito se odnose na utjecaj porasta koncentracije stakleničkih plinova (vodene pare, ugljikovog dioksida, metana) u atmosferu. Zbog rastuće potrošnje fosilnih goriva, raste i koncentracija stakleničkih plinova što uzrokuje porast temperature, a to rezultira posljedicama poput otapanja ledenih pokrova, porasta razine oceana, zakiseljavanje oceana, sušenje šuma; samim time ugrožava se postojeći ekosustav i dolazi do neodrživosti postojećih društvenih odnosa na globalnoj razini. Znanstveno je dokazano da su promjene klime izazvale ozbiljne štete u svijetu. Prognoze za Hrvatsku nisu nimalo optimistične. One daju naglasak na probleme vezane za hidrološke prilike te očekivane opasnosti (porast temperature) i štete (poplave, bujice, plavljenje obalnog područja, suše). Vodoopskrba stanovništva priobalja i otoka ugrožena je zbog mogućnosti miješanja slane i slatke vode u krškim vodonosnicima. Različiti pristupi promjeni klime izazivaju nesuglasice, a svako istraživanje uzroka klimatskih promjena dovodi do većeg poznavanja osjetljivosti i krhkosti klimatskih prilika na Zemlji. Najvažnije je pronaći rješenje koje se odnosi na čovjeka te smanjiti njegov utjecaj na prihvatljivu razinu, a prirodne uzroke upoznati dovoljno za smanjivanje očekivanih opasnosti.For years, experts have been studying causes of climate change. According to knowledge so far gathered, the causes of climate change may be natural, but also anthropogenic. When it comes to natural causes, we have Milankovitch cycles (variations in eccentricity, axial tilt, and precession of the Earth's orbit) which are active in relatively regular intervals. Solar radiation intensity, which is cyclic, the ENSO phenomenon, which consists of El Niño and La Niña, solid particles of volcanic ash and wildfire are also among the natural causes of climate change. Anthropogenic causes are mainly associated with the increase of greenhouse gas concentration (water vapor, carbon dioxide and methane) in the atmosphere. The concentration of greenhouse gasses increases because of the growing consumption of fossil fuels, which causes a rise in temperature, which then leads to the melting of ice caps, sea level rise, ocean acidification, the drying of forests; this endangers the existing ecosystem and leads to the unsustainability of present social relations on a global level. It is scientifically proven that climate change has caused serious damage in the world. Predictions for Croatia are not at all optimistic. They accentuate problems connected with hydrological conditions and anticipated dangers (the rise in temperature) as well as damage (floods, downpours, the flooding of coastal areas, droughts). Water supply to inhabitants of coastal areas and islands is jeopardized due to the possibility of mixing of fresh and salt water in karst aquifers. Different approaches to climate change cause disputes, and every study on causes of climate change leads to a greater understanding of the delicacy and fragility of climate conditions on Earth. The most important thing is to find a solution regarding man and to decrease his influence to an acceptable level, as well as to get acquainted with natural causes in order to decrease the anticipated dangers