source:http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data3.cfm/region=6_europe_wmo_region_6/country=GRC/cname=Greece -EnergyPlus Weather Converter V7.1.0.010
Statistics for GRC_Thessaloniki.166220_IWEC
Location -- THESSALONIKI - GRC
{N 40° 31'} {E 22° 58'} {GMT +2.0 Hours}
Elevation -- 4m above sea level
Standard Pressure at Elevation -- 101277Pa
Data Source -- IWEC Data
WMO Station 166220
1984-1990
Statistics for GRC_Thessaloniki.166220_IWEC
Location -- THESSALONIKI - GRC
{N 40° 31'} {E 22° 58'} {GMT +2.0 Hours}
Elevation -- 4m above sea level
Standard Pressure at Elevation -- 101277Pa
Data Source -- IWEC Data
WMO Station 166220
1984-1990
TEMPERATURE (°C)
temperature: is the condition of a body that determines whether heat shall flow from it. (unit °K - in this case °C)
refernece randall book
refernece randall book
Temperature range:
Highest average temperatures in June,July & August
June temperature ranges: 28> °C >18, average temperature = 23.5°C
July temperature ranges: 32>°C>20, average temperature = 26°C
August temperature ranges: 31>°C>21, with an average of 25.5°C
Lowest average temperature in December, January & February
December temperature ranges: 4 < °C <10, average temperature = 7.5°C
January temperature ranges: 3.5>°C<9.9, average temperature = 6°C
February temperature ranges: 2<°C<11.5, with an average of 6.5°C
Highest average temperatures in June,July & August
June temperature ranges: 28> °C >18, average temperature = 23.5°C
July temperature ranges: 32>°C>20, average temperature = 26°C
August temperature ranges: 31>°C>21, with an average of 25.5°C
Lowest average temperature in December, January & February
December temperature ranges: 4 < °C <10, average temperature = 7.5°C
January temperature ranges: 3.5>°C<9.9, average temperature = 6°C
February temperature ranges: 2<°C<11.5, with an average of 6.5°C
TEMPERATURE (°C) / RADIATION (Wh/m²)
Global horizontal radiation: refers to the total irradiance (often referred to as the global horizontal irradiance) is the sum of the direct radiation (beam radiation) and diffuse components
Direct normal radiation:is the amount of solar radiation received per unit area by a surface that is always held perpendicular (or normal) to the rays that come in a straight line from the direction of the sun at its current position in the sky. Typically, you can maximize the amount of irradiance annually received by a surface by keeping it normal to incoming radiation. (This quantity is of particular interest to concentrating solar thermal installations and installations that track the position of the sun.)
Diffuse Radiation: is radiation that has been scattered by atmosphere which includes constituents clouds, particulates, aerosols...(The majority of the light striking the earth during cloudy conditions is diffuse solar radiation)
Direct normal radiation:is the amount of solar radiation received per unit area by a surface that is always held perpendicular (or normal) to the rays that come in a straight line from the direction of the sun at its current position in the sky. Typically, you can maximize the amount of irradiance annually received by a surface by keeping it normal to incoming radiation. (This quantity is of particular interest to concentrating solar thermal installations and installations that track the position of the sun.)
Diffuse Radiation: is radiation that has been scattered by atmosphere which includes constituents clouds, particulates, aerosols...(The majority of the light striking the earth during cloudy conditions is diffuse solar radiation)
RADIATION RANGE (Wh/m²)
ILLUMINATION RANGE (lux)
SKY COVER RANGE / CLOUD COVER
Without a cloud cover in an area the temperature drops sharply at night whereas with clouds the temperature drop is noticeably more moderate. On the other hand in the daytime in the summer with no clouds the temperature goes much higher than it does when there is a cloud cover.
Global Horizontal Irradiance is the total amount of shortwave radiation received from above by a surface horizontal to the ground.
DIRECT NORMAL IRRADIANCE is solar radiation that comes in a straight line from the direction of the sun at its current position in the sky. DIFFUSE HORIZONTAL RADIATION is solar radiation that does not arrive on a direct path from the sun, but has been scattered by molecules and particles in the atmosphere and comes equally from all directions.
On a clear day, most of the solar radiation received by a horizontal surface will be Direct normal irradiance, while on a cloudy day most will be iffuuse horizontal irradiance.
DIRECT NORMAL IRRADIANCE is solar radiation that comes in a straight line from the direction of the sun at its current position in the sky. DIFFUSE HORIZONTAL RADIATION is solar radiation that does not arrive on a direct path from the sun, but has been scattered by molecules and particles in the atmosphere and comes equally from all directions.
On a clear day, most of the solar radiation received by a horizontal surface will be Direct normal irradiance, while on a cloudy day most will be iffuuse horizontal irradiance.
![Picture](/uploads/2/4/2/4/24247322/524039.png)
The effect of clouds on surface temperature is the net effect of 3 things:
- Their reflecting sunlight from their top side
- Their greenhouse effect of absorbing and radiating downward the thermal radiation of the Earth's surface
- Their reflecting back down the thermal radiation from the Earth's surface
- (http://www.sjsu.edu/faculty/watkins/cloudiness.htm)
RELATIVE HUMIDITY
Relative humidity: is the ratio of the current absolute humidity to the highest possible absolute humidity (which depends on the current air temperature). A reading of 100 percent relative humidity means that the air is totally saturated with water vapor and cannot hold any more, creating the possibility of rain. This doesn't mean that the relative humidity must be 100 percent in order for it to rain .(The hotter the air is, the more water it can contain.)
If the air is at 100-percent relative humidity, sweat will not evaporate into the air. As a result, we feel much hotter than the actual temperature when the relative humidity is high.
Summer months: 38% <relative humidity <70% (approximate values)
Winter months: 60% < relative humidity < 90% (approximate values)
If the air is at 100-percent relative humidity, sweat will not evaporate into the air. As a result, we feel much hotter than the actual temperature when the relative humidity is high.
Summer months: 38% <relative humidity <70% (approximate values)
Winter months: 60% < relative humidity < 90% (approximate values)
DEW POINT
Warm air can hold more water than cold air. Then dew point makes sense
Dew point and relative humidity are related. Dew point is measured in degrees of temperature. It is the temperature to which the present air would have to be lowered to become saturated... to be holding all the water it can hold. The greater the temperature/dewpoint spread, the less the amount of water in the air compared to how much it could hold
DEW POINT TEMPERATURE RANGES: 2°C (dry) / 18°C (muggy)
Dew point and relative humidity are related. Dew point is measured in degrees of temperature. It is the temperature to which the present air would have to be lowered to become saturated... to be holding all the water it can hold. The greater the temperature/dewpoint spread, the less the amount of water in the air compared to how much it could hold
DEW POINT TEMPERATURE RANGES: 2°C (dry) / 18°C (muggy)