Determination of particulate matter vertical columns using satellite observations

A new technique to retrieve the particulate matter vertical columns from spaceborne observations is described. The method is based on the measurements of the spectral aerosol optical thickness (AOT). The spectral slope of the derived aerosol optical thickness is used to infer the size of particles, which is needed (along with the absolute value of AOT) to determine corresponding vertical columns. The technique is applied to the case of a cloudless atmosphere over Germany and results are compared with ground-based observations. Several assumptions are made in the retrieval process such as the prescribed phase function, single scattering albedo, the refractive index of aerosol, and the half-width of the size distribution

Speeding up the AOT retrieval procedure using RTT analytical solutions: FAR code

Ugljen je neobnovljivi izvor energije i fosilno gorivo bez kojeg je teško zamisliti da bi svijet mogao funkcionirati na način na koji funkcionira danas. Ugljen je danas drugi energent u svijetu za proizvodnju primarne energije. Veliku važnost ugljen ima u proizvodnji električne energije, te u proizvodnji čelika i metala. Iz godine u godinu globalna potreba za energijom raste, najviše u gospodarstvima koja se naglo razvijaju i industrijaliziraju, te tako problemi vezani za energetsku sigurnost postaju sve važniji. Ugljen se smatra sigurnim energentom u proizvodnji energije jer su njegove rezerve u svijetu velike, a i cjenovno je prihvatljiviji od drugih fosilnih goriva. Pretvorba ugljena u električnu energiju odvija se u termoelektranama gdje prilikom izgaranja ugljena dolazi do emisija štetnih plinova u atmosferu koji pridonose klimatskim promjenama. Zbog onečišćenja koje uzrokuje ugljen svijet se sve više okreće proizvodnji energije iz obnovljivih izvora energija, ali se proizvodnja električne energije iz ugljena trenutačno ne može nadomjestiti iz obnovljivih izvora energije zbog velike ovisnosti o vremenskim uvjetima i financijskom ulaganju. Posljednjih godina sve se više spominje proizvodnja „čiste energije iz ugljena“ kako bi to bilo ostvarivo razvijaju se i primjenjuju brojne metode koje vode do toga. Preko 70% svjetske proizvodnje i potrošnje ugljena odvija se u Aziji, gdje se kao najveći potrošač i proizvođač istiće Kina koja većinu svoje energije proizvodi iz ugljena zbog njegove raspoloživosti i cijene.Coal is a non-renewable source of energy and a fossil fuel without which is hard to imagine the world could function at the way it does today. Today coal is the second energy source in the world to produce primary energy. Coal has high importance in the electricity production and production of steel and metals. Year by year the global demand for energy is growing, mostly in economies who rapidly develop and industrialize, and also problems related to energy security are becoming increasingly important. Coal is considered a safe source of energy in energy production because its reserves in the world are large, and the price is more acceptable than other fossil fuels. The conversion process of coal into electricity takes place in thermal power plants where, during the combustion of coal, comes to greenhouse gas emissions into the atmosphere which contributes to climate change. Due to the pollution caused by coal, the world is increasingly turning to the production of energy from renewable energy sources, but the generation of electricity from coal currently cannot be replaced by renewable energy because of its high dependence on weather conditions and financial investment. In recent years, there has been an increasing reference to the production of "clean coal energy" to make it feasible, many methods are being developed and applied which leads to it. Over 70% of the world's coal production and consumption takes place in Asia, where China is the largest consumer and producer of energy, which most energy producing from coal, because of availability and price

Algorithm to retrieve the melt pond fraction and the spectral albedo of Arctic summer ice from satellite optical data

A new algorithmto retrieve characteristics (albedo and melt pond fraction) of summer ice in the Arctic fromoptical satellite data is described. In contrast to other algorithms this algorithm does not use a priori values of the spectral albedo of the sea-ice constituents (such asmelt ponds,white ice etc.). Instead, it is based on an analytical solution for the reflection from sea ice surface. The algorithm includes the correction of the sought-for ice and ponds characteristics with the iterative procedure based on the Newton–Raphson method. Also, it accounts for the bi-directional reflection from the ice/snow surface, which is particularly important for Arctic regions where the sun is low. The algorithm includes an original procedure for the atmospheric correction, as well. This algorithm is implemented as computer code called Melt Pond Detector (MPD). The input to the current version of the MPD algorithm is the MERIS Level 1B data, including the radiance coefficients at ten wavelengths and the solar and observation angles (zenith and azimuth). Also, specific parameters describing surface and atmospheric state can be set in a configuration input file. The software output is the map of the melt ponds area fraction and the spectral albedo of sea-ice in HDF5 format. The numerical verification shows that theMPD algorithm provides more accurate results for the light ponds than for the dark ones. The spectral albedo is retrieved with high accuracy for any type of ice and ponds