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Reprinted from Journal of Atmospheric Sciences, Vol. 23, No. 6, pp. 678-681, November 1966. ; Research supported by the Air Force Cambridge Research Laboratories, Office of Aerospace Research, United States Air Force, L.G. Hanscom Field, Bedford, Massachusetts. ; Meteorology Laboratory Project 7655. ; "February 1967." ; Includes bibliographical references. ; Mode of access: Internet.

In the article, trends of lead content in atmospheric air of background territories and cities of Belarus according to NSEM data and their correlation with trends of lead content in the atmospheric air of cities and background territories of Europe and the USA are analyzed. Clear downward trends in lead content in the atmospheric air of the background territories of Belarus are shown: the average annual concentration of lead has decreased over the period from 1990 to 2015 by 77 %. According to EMEP stations measuring data having a continuous series of lead observations in atmospheric air since 1990, the mean annual lead content in atmospheric air at these stations decreased till 2013 on average by 86 %. A downward trend in the lead content was observed in the air of Belarusian cities and of some countries of Europe. The most significant decrease in lead content occurred in the USA, where the average annual maximum 3-month concentration decreased from 1990 to 2016 by 99 %. The relationship between trends in lead levels with trends of anthropogenic emissions is analyzed. Differences between the measured lead concentrations and calculated values by dispersion models are shown, which may be due to the incompleteness of the inventory of lead emissions in a number of countries, as well as the significant contribution of other sources of emission in addition to anthropogenic sources of lead emission into the atmosphere. To identify the reasons for these discrepancies, which may be related to the presence of unrecorded anthropogenic sources, secondary and natural sources, and other factors, additional research is needed.

In order to determine the highest surface air temperature at which standardized military materiel should be able to operate, world maps showing frequency of exceedance of various high temperatures are needed. Ideally these should be prepared by plotting probabilities of exceedance from frequency distributions of hourly temperatures, but such frequency distributions are not available on a world wide basis. An index was devised that could be related to temperatures exceeded 1, 5, and 10% of the time. The index is the sum of the mean and the mean daily range of temperature for the warmest month. The three relationships obtained were applied to estimate and map temperatures exceeded with the stated frequencies for 450 of the warmest locations of the world. Conclusions are drawn as to the interpretation of various temperature limits. (Author). ; Research supported by the Air Force Cambridge Research Laboratories, Office of Aerospace Research, United States Air Force, L.G. Hanscom Field, Bedford, Massachusetts. ; Aerospace Instrumentation Laboratory, Project 8624. ; AD0696094 (from http://www.dtic.mil). ; "August 1969." ; Includes bibliographical references (page 31). ; In order to determine the highest surface air temperature at which standardized military materiel should be able to operate, world maps showing frequency of exceedance of various high temperatures are needed. Ideally these should be prepared by plotting probabilities of exceedance from frequency distributions of hourly temperatures, but such frequency distributions are not available on a world wide basis. An index was devised that could be related to temperatures exceeded 1, 5, and 10% of the time. The index is the sum of the mean and the mean daily range of temperature for the warmest month. The three relationships obtained were applied to estimate and map temperatures exceeded with the stated frequencies for 450 of the warmest locations of the world. Conclusions are drawn as to the interpretation of various temperature limits. (Author). ; Mode of access: Internet.

I. Review of Basic Concepts and Systems of Units -- 1.1. Systems -- 1.2. Properties -- 1.3. Composition and State of a System -- 1.4. Equilibrium -- 1.5. Temperature. Temperature Scales -- 1.6. Systems of Units -- 1.7. Work of Expansion -- 1.8. Modifications and Processes. Reversibility -- 1.9. State Variables and State Functions. Equation of State -- 1.10. Equation of State for Gases -- 1.11. Mixture of Ideal Gases -- 1.12. Atmospheric Air Composition -- Problems -- II. The First Principle of Thermodynamics -- 2.1. Internal Energy -- 2.2. Heat -- 2.3. The First Principle. Enthalpy -- 2.4. Expressions of Q. Heat Capacities -- 2.5. Calculation of Internal Energy and Enthalpy -- 2.6. Latent Heats of Pure Substances. Kirchhoff's Equation -- 2.7. Adiabatic Processes in Ideal Gases. Potential Temperature -- 2.8. Polytropic Processes -- Problems -- III. The Second Principle of Thermodynamics -- 3.1. The Entropy -- 3.2. Thermodynamic Scale of Absolute Temperature -- 3.3. Formulations of the Second Principle -- 3.4. Lord Kelvin's and Clausius' Statements of the Second Principle -- 3.5. Joint Mathematical Expressions of the First and Second Principles. Thermodynamic Potentials -- 3.6. Equilibrium Conditions and the Sense of Natural Processes -- 3.7. Calculation of Entropy -- 3.8. Thermodynamic Equations of State. Calculation of Internal Energy and Enthalpy -- 3.9. Thermodynamic Functions of Ideal Gases -- 3.10. Entropy of Mixing for Ideal Gases -- 3.11. Difference Between Heat Capacities at Constant Pressure and at Constant Volume -- Problems -- IV. Water-Air Systems -- 4.1. Heterogeneous Systems -- 4.2. Fundamental Equations for Open Systems -- 4.3. Equations for the Heterogeneous System. Internal Equilibrium -- 4.4. Summary of Basic Formulas for Heterogeneous Systems -- 4.5. Number of Independent Variables -- 4.6. Phase-Transition Equilibria for Water -- 4.7. Thermodynamic Surface for Water Substance -- 4.8. Clausius-Clapeyron Equation -- 4.9. Water Vapor and Moist Air -- 4.10. Humidity Variables -- 4.11. Heat Capacities of Moist Air -- 4.12. Moist Air Adiabats -- 4.13. Enthalpy, Internal Energy and Entropy of Moist Air and of a Cloud -- Problems -- V. Aerological Diagrams -- 5.1. Purpose of Aerological Diagrams and Selection of Coordinates -- 5.2. Clapeyron Diagram -- 5.3. Tephigram -- 5.4. Curves for Saturated Adiabatic Expansion. Relative Orientation of Fundamental Lines -- 5.5. Emagram or Neuhoff Diagram -- 5.6. Refsdal Diagram -- 5.7. Pseudoadiabatic or Stüve Diagram -- 5.8. Area Equivalence -- 5.9. Summary of Diagrams -- 5.10. Determination of Mixing Ratio from the Relative Humidity -- 5.11. Area Computation and Energy Integrals -- Problems -- VI. Thermodynamic Processes in the Atmosphere -- 6.1. Isobaric Cooling. Dew and Frost Points -- 6.2. Condensation in the Atmosphere by Isobaric Cooling -- 6.3. Adiabatic Isobaric (Isenthalpic) Processes. Equivalent and Wet-Bulb Temperatures -- 6.4. Adiabatic Isobaric Mixing (Horizontal Mixing) Without Condensation -- 6.5. Adiabatic Isobaric Mixing with Condensation -- 6.6. Adiabatic Expansion in the Atmosphere -- 6.7. Saturation of Air by Adiabatic Ascent -- 6.8. Reversible Saturated Adiabatic Process -- 6.9. Pseudoadiabatic Process -- 6.10. Effect of Freezing in a Cloud -- 6.11. Vertical Mixing -- 6.12. Pseudo- or Adiabatic Equivalent and Wet-Bulb Temperatures -- 6.13. Summary of Temperature and Humidity Parameters. Conservative Properties -- Problems -- VII. Atmospheric Statics -- 7.1. The Geopotential Field -- 7.2. The Hydrostatic Equation -- 7.3. Equipotential and Isobaric Surfaces. Dynamic and Geopotential Height -- 7.4. Thermal Gradients -- 7.5. Constant-Lapse-Rate Atmospheres -- 7.6. Atmosphere of Homogeneous Density -- 7.7. Dry-Adiabatic Atmosphere -- 7.8. Isothermal Atmosphere -- 7.9. Standard Atmosphere -- 7.10. Altimeter -- 7.11. Integration of the Hydrostatic Equation -- Problems -- VIII. Vertical Stability -- 8.1. The Parcel Method -- 8.2. Stability Criteria -- 8.3. Lapse Rates for Dry, Moist and Saturated Adiabatic Ascents -- 8.4. The Lapse Rates of the Parcel and of the Environment -- 8.5. Stability Criteria for Adiabatic Processes -- 8.6. Conditional Instability -- 8.7. Oscillations in a Stable Layer -- 8.8. The Layer Method for Analyzing Stability -- 8.9. Entrainment -- 8.10. Potential or Convective Instability -- 8.11. Processes Producing Stability Changes for Dry Air -- 8.12. Stability Parameters of Saturated and Unsaturated Air, and Their Time Changes -- 8.13. Radiative Processes and Their Thermodynamic Consequences -- 8.14. Maximum Rate of Precipitation -- 8.15. Internal and Potential Energy of the Atmosphere -- 8.16. Internal and Potential Energy of a Layer with Constant Lapse Rate -- 8.17. Margules' Calculations on Overturning Air Masses -- 8.18. Transformations of a Layer with Constant Lapse Rate -- 8.19. The Available Potential Energy -- Problems -- Appendix I -- Answers to Problems.

Military equipment must be designed to operate at very cold temperatures, at extremes that have a small probability of being attained, perhaps only a few hours a month. The percentage of time during the coldest month that temperatures as cold or colder than -40, -50, -60, and -70F are estimated and mapped for the Northern Hemisphere. Maps of 1, 2, 5, 10 and 20 percent probable low temperatures for the coldest month, based on actual hourly temperature distributions, were available for North America, so that only Greenland and Eurasia needed mapping for completion of the Northern Hemisphere. This was accomplished by developing regression equations which related the departure of the 1,5,10 and 20 percentile lowest hourly temperatures from the monthly mean to the mean daily range of temperature; also, estimates of hourly percentile values of low temperatures were made from available six hour temperature distributions for several stations in Siberia. (Author). ; Research supported by the Air Force Cambridge Research Laboratories, Office of Aerospace Research, United States Air Force, L.G. Hanscom Field, Bedford, Massachusetts. ; Aerospace Instrumentation Laboratory Project 8624. ; AD0707092 (from http://www.dtic.mil). ; "March 1970." ; Includes bibliographical references (page 15). ; Military equipment must be designed to operate at very cold temperatures, at extremes that have a small probability of being attained, perhaps only a few hours a month. The percentage of time during the coldest month that temperatures as cold or colder than -40, -50, -60, and -70F are estimated and mapped for the Northern Hemisphere. Maps of 1, 2, 5, 10 and 20 percent probable low temperatures for the coldest month, based on actual hourly temperature distributions, were available for North America, so that only Greenland and Eurasia needed mapping for completion of the Northern Hemisphere. This was accomplished by developing regression equations which related the departure of the 1,5,10 and 20 percentile lowest hourly temperatures from the monthly mean to the mean daily range of temperature; also, estimates of hourly percentile values of low temperatures were made from available six hour temperature distributions for several stations in Siberia. (Author). ; Mode of access: Internet.

Abstract. As temperature extremes have a deep impact on environment, hydrology, agriculture, society and economy, the analysis of the mechanisms underlying their occurrence, including their relationships with the large-scale atmospheric circulation, is particularly pertinent and is discussed here for Europe and in the period 1961–2010 (50 yr). For this aim, a canonical correlation analysis, coupled with a principal component analysis (BPCCA), is applied between the monthly mean sea level pressure fields, defined within a large Euro-Atlantic sector, and the monthly occurrences of two temperature extreme indices (TN10p – cold nights and TX90p – warm days) in Europe. Each co-variability mode represents a large-scale forcing on the occurrence of temperature extremes. North Atlantic Oscillation-like patterns and strong anomalies in the atmospheric flow westwards of the British Isles are leading couplings between large-scale atmospheric circulation and winter, spring and autumn occurrences of both cold nights and warm days in Europe. Although summer couplings depict lower coherence between warm and cold events, important atmospheric anomalies are key driving mechanisms. For a better characterization of the extremes, the main features of the statistical distributions of the absolute minima (TNN) and maxima (TXX) are also examined for each season. Furthermore, statistically significant downward (upward) trends are detected in the cold night (warm day) occurrences over the period 1961–2010 throughout Europe, particularly in summer, which is in clear agreement with the overall warming.

The article presents the results of spatial and temporal dynamics research of the air temperature fields on the territory of the Crimean Peninsula due to the change of circulation epochs and periods of the Northern Hemisphere. Average multiannual maps of air temperature on the Crimean Peninsula for each circulating epoch and period were obtained, as well as maps of temperature fields dynamics at their change. Based on the obtained analysis of the maps it was found out that change in air temperature occurred not synchronously, but had its own characteristics in different regions of the Crimean Peninsula, which is explained by the influence of local factors. Zones characterized by constant maximum air temperatures in all considered periods have been recorded. It was found that during the instrumental observations on the Crimean Peninsula the warming occurred by 1 °C. This warming was occurring during the last circulation period.

Abstract
The following article presents the results of research on the influence of atmospheric circulation on air temperature and atmospheric precipitation in the Bydgoszcz-Toruń region (Poland) in the period 1921-2000. In order to do this, we have constructed a daily calendar of synoptic situations using criteria proposed by Niedźwiedź (1981). Daily values of air temperature and atmospheric precipitation were collected from the meteorological station in Toruń. Research results show that weather conditions in the study area are influenced predominantly by the direction of air mass advection and, to a lesser extent, by the prevailing type of isobaric system.