Naslov
Importance of volcanic activity in climate change models

Autori
Belobrk, Petra ; Brigljević, Zita ; Medunić, Gordana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
Meteorološki izazovi 3/Ekstremne vremenske prilike i utjecaj na društvo Challenges in meteorology 3/Extreme weather and impact on society

Mjesto i datum
Zagreb, Hrvatska, 21.11.2013. - 22.11.2013

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
volcanic eruptions; sulfate aerosol; Earth's climate; modeling

Sažetak
Numerical simulation models have widespread use in the earth sciences, e.g. geochemistry, hydrology, oceanography, and meteorology. Predicting the Earth's climate in response to increased concentrations of greenhouse gases is a basis for public policy decisions. Since climate encompasses complex physical processes, its modeling is still a question of significant debate as future climate projections are coupled with uncertainties. Increasing research on paleo-temperature reconstructions retrieved from the ice-core and deep-sea sediment records provide a wealth of data, and new insights into potential causes of global climate change over the geological past, which predictive value has still to be proven. As regards the many factors which regulate Earth's climate throughout time, volcanic eruptions and subsequent sulfate aerosol production have been linked with a cooling effect on climate. They affect the transparency of the atmosphere to sunlight and hence mo dify the regional and global climate. Although the amount by which they cool the planet is uncertain, their inclusion in climate change models substantially lowers the rate of temperature increase. Great volcanic eruptions commonly eject rocks, volcanic ash, and gases, like CO2, H2S, H2O, SO2, COS, CS2, HCl, HBr, HF. Ash is dispersed throughout the globe, carried by the winds, and then washed out by the rain in a few months. HBr is known for its enormous ozone depletion potential, which is more severe than that of chlorine. HF leads to acid rain development which is hazardous to plants and animals alike. On the other hand, particles of sulfuric acid absorb no sunlight, travelling hundreds of kilometers downwind. Their net effect in general is cooling of Earth's climate. For such an eruption to have an impact on the atmosphere, the volcanic column must be at least 10 - 20 km tall, thus contributing to particles high up in the atmosphere which scatter the solar energy back into space, and cause the cooling of that part of the atmosphere. However, those closer to the Earth's surface absorb the light, thus contributing to the greenhouse effect.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA