Organic NOX compounds

The direct natural emission of oxidized organic nitrogen compounds is unknown. Therefore, organic nitrites and nitrates are produced in the decomposition process of hydrocarbons (Chapter 5.7) where different oxo and carbon (alkyl) radicals can add NO (leading to nitrites) and NO2 (leading to nitrates Fig. 5.9) CH3O + NO + M CH3ONO + M (5.250) k5.250 3.3 1011 cm3 molecule-1 s-1 CH3O + NO2 + M CH3ONO2 + M (5.251) k5.251 2.1 1011 cm3 molecule-1 s-1 Organic peroxo radicals also add NO, where the...

Nitrogen

Even though the atmosphere is 78 nitrogen (N2), most biological systems are nitrogen limited on a physiological timescale because most biota are unable to use molecular nitrogen (N2). Two natural processes convert nonreactive N2 to reactive N lightning and biological fixation. Reactive nitrogen is defined as any single nitrogen species with the exception of N2 and N2O. It includes - NOy (NO + NO2 + N2O3 + N2O4 + HNO2 + HNO3 + NO3 + N2O5 + HNO4 + organic NOx + particulate NO- and NO-), - organic...

A4 Biography

Adh mar, Joseph-Alphonse (1797-1862) French mathematician his theory on ice ages was further developed and greatly modified, first by James Croll and later by Milutin Milan-kovic. Aitken, John (1839-1919) Scottish physicist and meteorologist in Edinburgh, one of the founders of cloud physics and aerosol science. al-Khazini, Abd al-Rahman (flourished 1115-1130) Greek Muslim scientist, astronomer, physicist, biologist, alchemist, mathematician and philosopher from Merv, then in the Khorasan...

T

Fig. 2.28 The biogeochemical sulfur cycle. A burial (formation of sediments), B assimilation (bacterial sulfate reduction), C aerobic oxidation, D deposition, E emission, M mineralization, P plant assimilation, O oxidation. N2), for sulfur the largest pool is the oceans (as dissolved sulfate) both components are chemically stable. In air, carbonyl sulfide (COS) represents the major sulfur component, due to its long residence time. Similarly to nitrogen and carbon, the sulfur content in the...

Properties of droplets

In Chapter 2.5.3, the phenomena of atmospheric water are described from a meteorological and hydrological point of view. Here, the physicochemical properties of droplets that are important for an understanding of cloud physics and chemistry will briefly be described. Atmospheric droplets are always solutions of gases and salts and partly suspended particles. Key properties such as the size and salinity of droplets are dominantly determined by the CCN (Chapter 4.3.5). Although droplets can...

Atmospheric acidity

In atmospheric waters (cloud, fog and raindroplets), the following 10 main ions must be taken into account SO2-, NO3-, Cl-, HCO-, NH+, Ca2+, Mg2+, Na+, K+ and H+ (Granat 1972, Moller and Zierath 1986, Moller and Horvath 1989). Of minor importance are HSO-, HSO-, SO -, NO-, CO -, F- and OH-. Because of the electroneutrality condition, the following cation, 2 aniony (4.181) must be valid17. In this and the following equations, only the equivalent concentrations will be used, otherwise the...

Hydrogen peroxide

Heikes et al. (1982) first suggested the idea of atmospheric aqueous phase H2O2 formation in cloud droplets. The in-droplet chemical formation of H2O2 occurs much faster than in the gas phase. However, one must consider the liquid volume fraction (LWC) ratio as well as the occurrence of clouds to assess the share of in- 18 Owing to its high sensitivity to humidity it is likely that heterogeneous surface reactions (e. g. O3 + H2O) forming oxidants also produced the color. 19 Fox (1873, pp....

A short history of understanding the process of photosynthesis

As we have seen, today's biosphere-atmosphere or, more simply, the plant-air interaction, is due to oxygenic photosynthesis. It is worth undertaking a short review of how our understanding of plant growth rose (Table 2.11). The main aim of this chapter is to touch upon the history of understanding the gas exchange between plant (biosphere) and air (atmosphere). As mentioned, oxygenic photosynthesis created the force for driving biogeochemical cycles. Plant growth has been both a curiosity and a...

The biosphere and the noosphere

The biosphere is considered to represent the earth's crust, atmosphere, oceans, and ice caps, and the living organisms that survive within this habitat (Hover 2006). Hence, the biosphere is more than a sphere in which life exists. It is the totality of living organisms with their environment, i.e., those layers of the earth and the earth's atmosphere in which living organisms are located. Another common definition such as the global sum of all ecosystems, however, calls for a definition of what...

Stratospheric oxygen chemistry

Chemistry in the stratosphere (which goes up to about 50 km in altitude) differs from that in the troposphere for three reasons (i) radiation below 300 nm is available for photodissociations that do not occur in the troposphere (Fig. 5.20), (ii) not all trace gases (those with a short lifetime) are either available or found in very Fig. 5.20 Penetration of solar UV radiation into the atmosphere as a function of wavelength and absorption by oxygen and ozone. The curve indicates the altitude at...

Historical remarks

Junge and Ryan (1958) first pointed out the importance of the atmospheric aqueous phase for SO2 oxidation. Although acid rain (Smith 1852), the bleaching properties of dew (Prout 1834) and hydrogen peroxide in rain (Meissner 1863) were known as phenomena many years ago, atmospheric aqueous phase chemistry has long been ignored compared with gas phase chemistry. Only the large air pollution relevance of sulfur dioxide in winter smog episodes stimulated relevant research in the 1950s (Chapter...

Sulfides H2S CS2 COS and RSH Reduced sulfur

In chemical textbooks, carbon disulfide and carbonyl sulfide are treated among carbon compounds. In the climate system, the contribution of CS2 and COS to the carbon budget is negligible and both species play no role in carbon chemistry. Moreover, COS only decomposes in the stratosphere because of its chemical stability. Most tropospheric COS is removed by dry deposition (plant assimilation and uptake by microorganisms in soils). Crutzen (1976) suggested COS to be a contributor to the...

CO The biomass burning problem

CO is primarily emitted through incomplete combustion processes (biomass burning, domestic combustion and traffic) and is likely to be biogenically produced from soils as well as being an important secondary product from NMVOC oxidation in the atmosphere. It has a lifetime of about 2-3 months, strongly depending on the OH concentration and thereby shows inversely correlated seasonal concentration Fig. 2.79 Atmospheric carbon monoxide record (monthly means, calculated as the mean of daily values...

Thermodynamic The equations of state

Thermodynamics was originally the study of the energy conversion between heat and mechanical work, but now tends to include macroscopic variables such as temperature, volume and pressure. In physics and chemistry, and thereby the atmosphere and more generally the climate system, thermodynamics includes all processes of equilibrium between water phases, including hydrometeors, trace gases and aerosol particles (APs). These processes occurring in energetic changes are the key factor for...

The gas laws

The gas laws developed by Robert Boyle, Jacques Charles and Joseph Gay-Lussac are based upon empirical observations and describe the behavior of a gas in macroscopic terms, that is, in terms of properties that a person can directly observe and experience. The kinetic theory of gases describes the behavior of molecules in a gas based on the mechanical movements of single molecules. A gas is defined as a collection of small particles (atom- and molecule-sized) with the mass mi (subscript i...

The rise of oxygen and ozone Biogeochemical evolution

Knowledge of the atmospheric composition and surface temperature throughout the Archean (2.5-4.0 Gyr) is essential for understanding the origin and early evolution of life on earth. Two factors should have inevitably affected this environment reduced solar luminosity and reduced levels of oxygen. The global geothermal heat flow was substantially higher during earth's first billion years (Turcotte 1980), and the vigorous geothermal outgassing probably dispersed reduced chemical species...

Dew frost rime and interception

In the last two sections we considered hydrometeors, drops and ice particles in clouds, fog, mist and precipitation. This section deals with the formation of interfacial water, either from water vapor (dew and frost) or from hydrometeors (rime and interception). These forms of atmospheric water need the contact with a surface soils and vegetation but also artificial surfaces. Some meteorologists classify these phenomena as belonging to precipitation - we will not (see Chapter 4.4 for more...

A1 List of acronyms and abbreviations found in literature1

ACPC aerosols, clouds, precipitation, climate program AOT accumulated dose over threshold BBOA biomass burning organic aerosol B.C. (also BC) before Christ, from the Latin Ante Christum, an epoch based on the traditionally reckoned year of the conception or birth of Jesus BECS bio-energy with carbon storage BOVOC biogenic oxygenated volatile organic carbon BP before present (also B.P., e. g. kyr BP - thousand years before present) Btu British thermal unit (sometimes also BTU) BVOC biogenic...

Info

Cation, we also have to compare one state with another reference state. In natural systems, the most appropriate reference state is that which relates to the system itself. Other reference states have no meaning (physically or chemically), but might be useful or even necessary from a computational point of view (Oden 1976). Other atmospheric ions originating from the natural emission of gaseous species and PM lead to a natural acidity Acj nat or alkalinity, which varies in time and space (e. g....

Climate and climatology A historical perspective

The term climate has been used over time in different senses. The ancient Greek word KXi a (clima) means area or region (clime) and is first found in the New Testament (Benseler and Schenkl 1900) the Greek philosophers did not use the word (Gilbert 1907). It is derived from kXivw (klinein) which means to incline (Latin inclino) and was probably first used in French in the late fourteenth century (climat) in the sense of zone. The ancient geographers and travellers used the term climata (plural...

The CO2carbonate system

In water, the following chemical carbon-IV species exist in equilibrium carbon dioxide (CO2), carbonic acid (H2CO3), bicarbonate (HCO3-) and carbonate (CO 32-). Additionally, the phase equilibriums with gaseous CO2 and a possible solid body such as CaCO3 and MgCO3 have to be considered. Free carbonic acid is not isolated but the structure O C(OH)2 in aqueous solution has been confirmed. Often the expression CO2 H2O is also used for carbonic acid. The sum of the dissolved carbonate species is...

Is the atmospheric fate of complex organic compounds predictable

In recent years, the availability of kinetic and mechanistic data relevant to the oxidation of VOCs has increased significantly and various aspects of the tropo-spheric chemistry of organic compounds have been reviewed extensively. We have a good generic VOC mechanism for the OH-initiated oxidation of organics that becomes progressively less accurate with increasing carbon number, functionaliza-tion (with oxygen) and especially at low NOX. What we do know is summarized in the master chemical...

Dust and acid rain Air pollution

With the intense industrial development in the middle of the nineteenth century, air pollution as a new atmospheric aspect became the object of interest of researchers more precisely, the impacts of air pollutant (forest decline, human health, cor rosion) were the first foci of research. Already in the late nineteenth century, some impacts could be related to individual air pollutants (cause-receptor relationship, e.g. Stockhardt 1850, 1871). The techniques available to measure trace species,...

Aqueous phase and interfacial chemistry

NO3, N2O5 and HNO3 will be quantitatively scavenged by natural waters. Nitric acid is a strong acid and thereby fully dissociated (Table 4.9), whereas nitrous acid is roughly 50 dissociated in hydrometeors. HNO2 NO- + H+ pKa 3.3 (5.193) When N2O5 sticks to the water's surface, it is completely and quickly converted into nitrate ions. The nitrate radical NO2 can react with all electron donors according to (5.194) and is therefore a strong oxidant It reacts with dissolved hydrocarbons (5.178) but...

Atmospheric removal Deposition processes

Deposition is the mass transfer from the atmosphere to the earth's surface it is the opposite of emission (the escape of chemical species from the earth's surface into the air). It is a flux given in mass per unit of area and unit of time. According to the various forms and reservoirs of atmospheric chemical species (molecules in the gas, particulate and liquid phases), different physical and chemical processes are distinguished - Sedimentation of matter because of the earth's gravitational...

Freezing point depression

The freezing point depression follows from the lowering of vapor pressure. From the Clausius-Clapeyron equation and Raoult's law, it follows (AsmH enthalpy of smelting) that Taking the molality m (defined as the ratio of the amount of dissolved matter and the mass of water, expressed in mol kg-1 and in contrast to the molarity not depending on T in dissolved solution molarity is proportional to molality) we obtain where Kf is the cryoscopic constant, which is empirical and can be determined...

Emission of atmospheric substances

An emission inventory is a database that lists, by source, the amount of air pollutants discharged into the atmosphere of a community during a given time period. As already emphasized several times, emissions as the flux (mass per time) of substances in the atmosphere are the key parameter for atmospheric chemistry - they determine the initial air concentration (the key parameter for the reaction rate) and the composition (the key parameter for the reaction mechanisms). Beginning with estimates...

Abiogenic versus biogenic formation of fossil fuels

It was previously noted that the net ecosystem production (NEP) nowadays is small or even negligible but it had a strong influence in the period when colonization of the continents by plants did occur. During this time, with still reduced oxygen, respiration was not yet significant and large quantities of GPP could be buried. As a result, coal, oil and natural gas have been formed and it seems unnecessary to go deeper in discussing the biogenic theory of fossil-fuel formation. None the less, it...

Photosynthesis Nonequilibrium redox processes

The basic principles of photosynthesis are presented in this Chapter 2.2.2.3 and the next one 2.2.2.4. Here we will discuss the chemical evolution of the assimilation process (see for definition what photosynthesis means the next Chapter 2.2.2.4). Let us understand as assimilation generally the conversion of nutrients into the fluid or solid substance of the body of an organism, by the processes of digestion and absorption. It is not the aim here to discuss biological chemistry (biochemistry),...

C2 chemistry C2H2 C2H4 C2H6 C2H5OH CH3CHO CH3Cooh Cooh2

From a single carbon, according to the scheme in Fig. 2.42, C2 (and higher) hydrocarbons are built up using the building blocks CH3 and CO. Alkanes (also known as paraffins), with the general formula CnH2n+2, represent CH2 chain blocks with methyl ends. They generally produce first an aldehyde by the OH oxidation of the terminal carbon atom and then a bicarbonyl at the other end of the chain (here C2). H3C CH3 - H3C C(O)H- (C(O)H)2 ( k h2o - no2 - ho2) (- h2o - no2 ho2) Acetaldehyde CH3CHO...

H2c2o5

A very weak acid forming b only as salts d isomer with the non-acidic glyoxal O CH CH O (ethandial) e IUPAC name ethanoic acid other names methanecarboxylic acid, acetyl hydroxide f IUPAC name 2-hydroxyethanoic acid, other name hydroxoacetic acid g IUPAC name oxoethanoic acid other names oxoacetic acid, formylformic acid (ubiquitous in nature in berries) a very weak acid forming b only as salts d isomer with the non-acidic glyoxal O CH CH O (ethandial) e IUPAC name ethanoic acid other names...

O M

Fig. 2.12 Composite database of solar irradiance compiled from many satellite TSI data 1978-present (daily means). I acknowledge the receipt of the dataset from PMOD WRC, Davos, Switzerland, and acknowledge unpublished data from the VIRGO Team (see e. g. Fr hlich and Lean 1998). Fig. 2.12 Composite database of solar irradiance compiled from many satellite TSI data 1978-present (daily means). I acknowledge the receipt of the dataset from PMOD WRC, Davos, Switzerland, and acknowledge unpublished...

Growth and equilibrium stationary state28

In nature, many processes follow this simple law (2.143), which expresses that the change of a quantity N (for example population, mass, energy) is proportional to the quantity itself. In other words, exponential growth occurs when some quantity regularly increases by a fixed percentage. The proportionality coefficient X characterizes the process (biology, chemistry, physics, economy, etc.) as follows dN d. n F and N(t) N0 exp (At) (2.143) We see that dN dt denotes a flux F according to the...

From Antiquity to the Renaissance Before the discovery of the composition of air

Before the sixth century B.C., air was identified as emptiness. Greek natural philosophers assigned air and water beside earth and fire to the four elements (in Latin, materia prima, primary matter). Thales of Miletus (624-546 B.C.) was the first person who is known to have tried to answer the question of how the universe could possibly be conceived as made not simply by gods and daemons. He defined water as a primary matter and regarded the earth as a disc within the endless sea. Pythagoras...

Y1iVm1 y2r2 y3rm3

In Eq. (4.86), k+ und k_ represent the rate constants of the partial processes and the forward (k+) and back (k_) reaction or transfer. Equilibrium also means that the fluxes of the forward and backward processes are equal F+ F_ because of dui dui and therefore dWT, V 0 and AGTp 0. Hence, it is valid that F+ (f )+ k+ XilV1 X2lV2 F- (f k- y1iVm+1 y2iVm+2 (4.88) In 1886, Jacob van't Hoff derived thermodynamically the law of mass action based on the work from the initial substances Xt and final...

Surface tension and surface active substances

An important property of the surfaces of droplets is the surface tension that expresses the cohesion of water molecules (Chapter 2.5.1.1). On molecules existing close to the droplet surface, forces are directed to the inner of the droplet. Therefore, each liquid has the tendency to form spherical particles (if they are not counteracting forces such as gravitation and other outer forces). The reason is simple a sphere of a given volume has the smallest surface of all bodies. Thus, a growing...

D

Fig. 2.99 Modular system of solar fuel production through CO2 utilization and cycling. sites where climatic conditions support large CO2 absorption (see above) and or to sites of CO2 processing. Solar power plants are decentralized close to urban and industrial areas (module D). Solar fuel (in contrast to CO2) can be easily transported and stored using traditional infrastructure for liquids and gases. Processing sites (module C) must have access to solar (or non-fossil) energy. Then, by using...

Oxides and oxoacids SO2 H2SO3 SO3 H2SO4

Out of biological chemistry, sulfur dioxide (and sulfurous acid) and sulfur trioxide (and sulfuric acid) are the dominant species remember that the only natural source of SO2 is given by volcanic activities25. Apart from minor global (but locally it can be a significant source) contributions from metallurgic processes, anthropogenic SO2 is exclusively from the combustion of fossil fuels, mainly coal. In the air, we have to consider gas phase SO2 oxidation and the following gas-to-particle...

Ci chemistry CO CO2 CH4 CH3Oh Hcho Hcooh

Most of the gas phase C1 chemistry is elsewhere presented (Chapters 5.3.2.2 and 5.3.3 concerns organic and 2.8.3.2 concerns CO2 and carbonate dissolution). Two species from the heading above, methanol CH3OH and formic acid HCOOH we met as emissions from biomass burning (Table 2.44). Because C O and O H bonds are much stronger than the C H bond, OH attack goes preferable onto C H (at higher carbon chains preferably at the a C H) k5.325 7.7 10-13 cm3 molecule-1 s-1 and k5 326 1.3 10-13 cm3...

O3play Key Role In What Atomsphere

Fig. 5.5 Chemical species and schematic relationships between Oj - O4 chemistry. Fig. 5.5 Chemical species and schematic relationships between Oj - O4 chemistry. ter between groups Ox and O2. Group O4 only plays a (hypothetical) transient state from O3 to O2. Hydrogen radicals (H) and ions (H+) are closely connected with oxygen chemistry in Chapter 4.2.4, we stated that H and O are the symbols for reduction and oxidation, respectively. In the troposphere, reactive oxygen species (ROS) are only...

Climate and the climate system

Within climatology, as the rather descriptive science of climate, the meteorological definition of climate has proved itself. For an understanding of the dynamics of climate, that is, the processes that determine the average state and the variability of the atmosphere over longer periods, the meteorological definition is inadequate, as over longer periods changes in the atmosphere are considerably affected by interde-pendencies of the atmosphere, the ocean, vegetation and ice masses (ClauBen...

Physical basics

The fundamental law of nature is the law of the conservation of matter. Matter occurs in two states flowing energy (Chapter 2.3) and cycling material (Chapter 2.4). The climate system, however, is an open system and is in permanent exchange with its surrounding earth system and thereby space (Fig. 3.2). Therefore, we generally expect changes and variations of internal energy and mass over time. From a chemical point of view, the interest lies in the quantification of the amount - in terms of...

Discovery of the composition of air and water

In the eighteenth century the interest in natural processes generally expanded. Travellers and biologists were interested in describing the climate and its relation to culture and biota, and in the late 1700s chemists began to understand the transformation between solid, liquid and gaseous matter. A fundamental interest in biological processes, such as plant growth, nutrition and respiration among others, stimulated the study of the water cycle and the gas exchange between plant and air. John...

Haze mist and fog

The atmosphere becomes milky through light scattering on particles in the size range between 50 and 200 nm. WMO uses for atmospheric obscuration the following terms Fog, Ice fog, Steam fog, Mist, Haze, Smoke, Volcanic ash, Dust, Sand, and Snow. With the exception of smoke, volcanic ash, dust and sand (all these are particles belonging to atmospheric aerosol) the other particles belong to hydromete-ors. Snow is precipitation (see the next section, Chapter 2.5.3.4) as a final fate of cloud...

Hydrological cycle and the climate system

In ancient Greek, dx tg (atmis water vapors) denotes the transfer of water (by evaporation) from the telluric form (hydrosphere) into d Q (aer), the water vapor of the atmosphere and its return as precipitation to the earth, (with water) one of the two lower elements. We know from Herodotus that in the fifth century B.C. this theory was known and accepted and described by Hippocrates. The long-term mean values for hydrological reservoirs and fluxes (as depicted in Table 2.22 and Fig. 2.35) are...

Aqueous and interfacial chemistry

A significant source of hydrogen and nitrosyl halogenides is the surface of sea salt. Sea salt aerosol SSA has multiple impacts besides other particulate matter categories on atmospheric properties responding to climate by optical properties Mahowald et al. 2006 , providing cloud condensation nuclei McGovern et al. 1994 Clarke et al. 2006 , being a heterogeneous surface for multiphase chemical reactions, e. g. SO2 oxidation Luria and Sievering 1991 and being a source for reactive chlorine...