ClimateClimate: sum of all statistical weather info that helps describe a place or region. It is a dynamic complex of meteorological andcosmic factors for a long period of time andis characterized by a middle expression of: Atmospheric pressure Air temperatute Air humidity Air velocity (winds) Sun radiation, Raining
The particularity of the climate are defined by: Geografic latitude and attitude Relief of the territory Vegetation (forests) Water reservoirs (see, lakes, rivers)
For more detailed evaluation the climate could be divided into: Macro-climate – in given geographic zone “Middle-climate” – in a given place “Micro-climate” – in closed rooms
The climatic zones are confined within the isothermal lines. These lines connect all points with equal annual air temperatures. - Tropical climate – between equator and 25°C isotherm- Subtropical climate - between 25°C and 15°C isotherm - Moderate climate - between 15°C and 5°C isotherm - Cold climate Bulgaria is in the moderate climate zone.
Weather Weather: State of the atmosphere at a given time and place; constantly changing. Weather is described by variables such as: Temperature Pressure Wind Speed and Direction Precipitation Cloud Cover
Depending on the meteorological factors WEATHER could be: Optimal – with small daily air temperature amplitude (2°C) and air velocity less than 3 m/s Irritating – one or more of the meteorological factors are out of their optimal levels; air velocity is up to 8 m/s; high daily air temperature amplitude Sharp – significant changes of meteorological factors
The adaptation of people to slow changes ofmeteorological factors is good, but isn’t such to sharp ones. More sensitive people could suffer some unfavorable health conditions likecardiovascular problems (hypertension), neuroses, arthritis, cerebro-vascular diseases, bronchial hypersensitivity. The prophylactic measures includehealthful style of living, training, healthy nutrition, suited clothing, medicaments.
What is the difference between weather and climate? Weather is what you see outside of the window, climate is the weather conditions of an area averaged over a long period (30 years)
Weather or Climate??? The average high temperature for the month of July in Chicago is 84oF. Cumulus clouds presently cover the entire sky. Snow is falling at a rate of 1 inch per hour. The summers here are warm and humid. At 3:00 p.m, winds were blowing from the NW. Total precipitation at O’Hare Airport for 2003 was 32.02 inches, which is 4.25 inches below normal.
How do we measure climate factors? Anemometer Wind and rain Gauge AneroidBarometer Radiosonde
Latitude (T) The further away from the equator" the colder it is. (P) Closer to the poles results in lower precipitation
Unequal Earth HeatingIncident light is spread over a greater area near thepoles, less heat is radiated from the earth.
Ocean Currents (T) When warm, they raise temperatures along the coast (especially in winter) and when cold, they lower temperatures (especially in summer) (P) When warm, they help to create wet coastal climates, when cold, they help to create drier coastal climates
Nearness to Water Maritime climates (by the ocean) are moderated (cooler summers, warmer winters) by the ocean. Precipitation is higher in maritime climates than in continental (inland) climates.
Review: World climate patterns Concepts: The earth heats unevenly Because of its tilt and the fact that it is a sphere This uneven heating drives global circulation There is predictable variability in climate, at local to global scales Because it is a sphere: Radiation is spread over more area at the high latitudes than at the equator
Hygienic characteristic of physical factors of atmosphere Physical factors of atmosphere could bedivided into:- Meteorological factors – atmospheric(barometric) pressure, air temperature,humidity, atmospheric electricity andionization of the air.- Factors, arising from the cosmos – sunradiation, heliomagnetic factors
Meteorological factors Atmospheric pressure It is an important factor in climate formation. Atmospheric pressure over the surfaces andbodies is due to the weight of air layers becauseof the gravitation. At the sea level, vertical air column of 1square sm. Has middle mass of 1013 g and isbalanced by Hg column with 760 mm altitude. Itis 1 atmosphere and is accepted as a normalvalue at the sea level.
Air pressure inside and outside the body has beenequalized by the respiratory tract with greateramounts of gases being absorbed to the tissues andcompressed into body cavities. As the atmospheric pressure is increased ordecreased some discomfort or diseases could bemanifested. 1. Health problems related with increasedatmospheric pressure Such could occur during work under water(diving, work in barocamera). During compressionthe following health efects could be manifested:
- Ear trauma – as a result of a relativevacuum in the middle ear – acute of chronicinflammation caused by a reduction in airpressure in the tympani cavity. There is afeeling of fullness in the ears, decreased sounddensity, discomfort and desire to “clear theears”. - The “squeeze” – dyspnea, heavysensation in the chest, a bulging sensation inthe head and eyes, edema and even smallhemorrhages in lungs, gastrointestinal tract,nose, ears and facial skin.
- Nitrogen narcosis – occurs at depthsgreater than 30 m. The symptoms arenumbness, discoordination, hallucinationsand unconsciousness – at depth over 90 m.These effects may be prevented bybreathing mixtures depleted in nitrogenby helium.
- Decompression sickness – during the decompression, when the organism is exposed again to surface atmosphericpressure, the compressed gases in the bodytend to come out of the solution. When it’s rapid, bubbles (primary of nitrogen) are formed in tissues and blood resulting in blockage of capillaries or even emboli. Symptoms depend on the localization of emboli (lungs, brain etc.). If the decompression is slow the gases can be exhaled without problems.
2. Health problems related with decreaseddecreased atmospheric pressure. They appearbecause of the diminished ambient pressure ofoxygen. - Acute mountain illness – very often quicklytransiting, manifested with headache, vomiting andimpaired vision. - High attitude pulmonary edema - the symptomsare usually manifested at the 3th day at highaltitude. At the beginning they are similar to these ofmountain disease, but further pulmonary edemadevelops with cough and even Cheyne-Stokesbreathing.
Air temperature Direct heating of air from the sun isunimportant – only about 0.02%. Air heating ismainly from the infrared irradiation from theground. Factors affecting air temperature are:- latitude of the place- altitude- direction of the wind- proximity of sea- big water reservoirs (lakes), vegetation zonesThe mean year temperature in Bulgaria is 11.5C
Air humidity The humidity of the air depend on itstemperature. Humidity could be expressed asabsolute and relative. Relative humidity isused more commonly in health practice. Air velocity A meteorological parameter, whichtogether with temperature and humidity of theair determine the microclimate at a certain areaand determining the thermal comfort.
Factors, arising from the cosmos A. Sun radiation The spectrum of sun radiation consists ofultraviolet radiation – UV (wave length under400 nm), visible radiation (400-760 nm) andinfrared radiation (over 760 nm). Health effects of UV radiation - Non – specific effects – stimulation ofprotein, lipid and carbohydrates metabolism,improved immunological reactivity, increasedmelanin production.
- Specific effects – short UV wavespossess bactericidal and mutagenic effects.Limited skin exposure to middle UV wavesresults in photochemical conversion of pro-vitamin D to the active compound.Cumulative effect of repetitiveoccupational exposure to long UV wavesmay cause cataract, retinal damage, skinerythema (sunburn) or skin cancer.
Effects of visible radiation (VR) Prolonged and intensive exposure to lightcould cause serious eye damage. Less traumaticeffect is astenopia (eye strain) – tired eye, visualdiscomfort, irritation, headache. Also, disturbanceof cardiac rhythm, influencing physical activity,sleep, food consumption etc. could appear. Effects of infrared radiation (IR)It penetrates skin and induces heating. IR maycause thermal damage of cornea, iris and retinallesions. Chronic, long-term exposure may causecataract.
B. Electromagnetic radiation It could be defined as a series of wavescomposed of oscillating electric and magneticfields traveling through space with the speedof light. Electromagnetic radiation cantransmit energy to biological molecules andaffect the biological systems. For example, theabsorbed energy could be transmitted to heatand increase the tissues temperature. The exactbiological effects depend on the characteristicof the radiation involved and the sensitivity ofthe organism.
Air ionization It is characterized the grade of formation ofpositive and negative air ions. The concentrationof positive air ions is increased in polluted urbanareas and indoor air. The concentration negative air ions is higher inmountains, wood areas, near the see andwaterfalls. They are indicator of air purity andhave favorable health effects.
Health effects of physical factors of the atmosphere Positive – negative air ions Negative - heat stroke (disturbed mechanisms of thermoregulation); - - sun stroke (directs exposure of head to sun); - heat exhaustion; - heat syncope; - effects of cold stress etc.