Climatic zones in india

climatology assignment

1. Climatic zones in india Submitted by Priya Bharti b.Arch Sem 4

2. INTRODUCTION India experiences varied climates ranging from tropical in the south to temperate and alpine in the Himalayan north. Snowfall is received by elevated areas during winters. India has Tropical monsoon type of climate. These varied climates occur due to vast area and latitudinal differences. Climate of India is divided into five different zones known as climate zones. Following are the name of climate zones of India: HOT AND DRY WARM AND HUMID MODERATE COLD AND CLOUDY CLOUD AND SUNNY COMPOSITE

3. HOT AND DRY ZONE HOT DRY WEATHER IN SUMMER AND COLD IN WINTER VERY LITTLE RAINFALL VERY LOW HUMIDITY SANDY OR ROCKY GROUND WITH VERY LOW VEGETATION COVER HIGH TEMP. DIFFERENCE BETWEEN NIGHT AND DAY HOT WINDS AND FREQUENT DUST-STORMS HIGH SUMMER DAY TIME TEMP.(32° C - 36 °C) • HIGH SOLAR RADIATION UNDER THIS ZONE ARE JAISALMER, JODHPUR AND SHOLAPUR

4. Warm and humid THE DIURNAL VARIATION IN TEMPERATURE IS QUITE LOW. IN SUMMER, TEMPERATURES CAN REACH AS HIGH AS 30 – 35 ºC DURING THE DAY, AND 25 – 30 ºC AT NIGHT. IN WINTER, THE MAXIMUM TEMPERATURE IS BETWEEN 25 TO 30 ºC DURING THE DAY AND 20 TO 25 ºC AT NIGHT. PRECIPITATION IS ALSO HIGH, BEING ABOUT 1200 MM PER YEAR, OR EVEN MORE THE WIND IS GENERALLY FROM ONE OR TWO PREVAILING DIRECTIONS WITH SPEEDS RANGING FROM EXTREMELY LOW TO VERY HIGH. CITIES UNDER THIS ZONE ARE MUMBAI, CHENNAI AND KOLKATA

5. moderate LOCATED ON HILLY OR HIGH-PLATEAU REGIONS WITH FAIRLY ABUNDANT VEGETATION. THE TEMPERATURES ARE NEITHER TOO HOT NOR TOO COLD. IN SUMMERS, THE TEMPERATURE REACHES 30 – 34 ºC DURING THE DAY AND 17 – 24 ºC AT NIGHT IN WINTER, THE MAXIMUM TEMPERATURE IS BETWEEN 27 TO 33 ºC DURING THE DAY AND 16 TO 18 ºC AT NIGHT. THE RELATIVE HUMIDITY IS LOW IN WINTERS AND SUMMERS, VARYING FROM 20 – 55%, AND GOING UPTO 55 – 90% DURING MONSOONS CITIES UNDER THIS ZONE ARE PUNE AND BANGALORE THE TOTAL RAINFALL USUALLY EXCEEDS 1000 MM PER YEAR.

6. Cold and sunny THE REGION IS MOUNTAINOUS, HAS LITTLE VEGETATION, AND IS CONSIDERED TO BE A COLD DESERT. IN SUMMER, THE TEMPERATURE REACHES 17– 24 ºC DURING THE DAY AND 4– 11 ºC AT NIGHT. IN WINTER, THE VALUES RANGE FROM -7 TO 8 ºC DURING THE DAY AND -14 TO 0 ºC AT NIGHT. THE RELATIVE HUMIDITY IS CONSISTENTLY LOW RANGING FROM ABOUT 10 – 50 % PRECIPITATION IS GENERALLY LESS THAN 200 MM PER YEAR COLD AND SUNNYTHE COLD AND SUNNY TYPE OF CLIMATE IS EXPERIENCED IN LEH (LADAKH).

7. Cold and cloudy MOST COLD AND CLOUDY REGIONS ARE SITUATED AT HIGH ALTITUDES IN SUMMER, THE MAXIMUM AMBIENT TEMPERATURE IS IN THE RANGE OF 20 – 30 ºC DURING THE DAY AND 17– 27 ºC AT NIGHT, MAKING SUMMERS QUITE PLEASANT IN WINTER, THE VALUES RANGE BETWEEN 4 AND 8 ºC DURING THE DAY AND FROM -3TO 4 ºC AT NIGHT, MAKING IT QUITE CHILLY. THE RELATIVE HUMIDITY IS GENERALLY HIGH AND RANGES FROM 70 – 80 %. ANNUAL TOTAL PRECIPITATION IS ABOUT 1000 MM AND IS DISTRIBUTED EVENLY THROUGHOUT THE YEAR. OOTACAMUND, SHIMLA, SHILLONG, SRINAGAR AND MAHABALESHWAR ARE EXAMPLES OF PLACES BELONGING TO THIS CLIMATIC ZONE.

8. composite The composite climate zone covers the central part of India . In summers day time temperature is 32-45 degree Celsius and during night time temperature is 27-32 degree Celsius. In winters day time temperature is 10-25 degree Celsius and in night time temperature is degree Celsius. Monsoon winds come from south-east and north-east.

9. Forms and planning Buildings can be ventilated and/or cooled by taking advantage of naturally occurring wind currents. Guidelines for cross ventilation: Locate inlet openings perpendicular to (or at most ±45° from) the prevailing winds. Locate outlet openings on the opposite side of inlet openings, and make them equal to, or greater in size than, the inlet openings. A building elongated in the east-west direction exposes the shorter east and west sides to maximum solar heat gain and high afternoon temperatures during warm months. Shape a building so that it: Is elongated in the east-west direction; and Has a narrow floor plate for incorporating cross or stack ventilation.

10. DESIGN STRATEGIES IN CLIMATE OF LUCKNOW • BUILDINGS SHOULD BE DESIGNED TO ACCOMPLISH BEST POSSIBLE INDOOR CLIMATIC ENVIRONMENT TO ATTAIN HUMAN COMFORT. • Lucknow lies in the composite climate zone according to NBC (National Building Code) which is characterized by extreme temperatures in summers and winters. • located between 26.30 & 27. 0 North and 80.30 & 81.13 East at an altitude of approximately 128m measured from the sea level

11. HEATING DEGREE DAYS AND COOLING DEGREE DAY ACCORDING TO ASHRAE (90.1), HEATING DEGREE DAYS BASE 65°F (HDD65) AND COOLING DEGREE DAYS BASE 50°F (CDD50) ARE CALCULATED FROM READINGS OF OUTSIDE AIR TEMPERATURE. THE ANNUAL HDD65 AND CDD50 FOR LUCKNOW IS 375 AND 9552 RESPECTIVELY CDD50 IS VERY HIGH CONSEQUENTLY, THE DESIGN STRATEGIES THAT REDUCES THE COOLING LOAD WOULD BE MORE HELPFUL THAN THE DESIGN STRATEGIES REDUCING THE HEATING LOAD

12. BUILDING DESIGN FEATURES DESIGNING A BUILDING ACCORDING TO CLIMATE HAS MULTIFOLD BENEFITS, FIRSTLY IT ENABLES THE USE OF NATURAL ENERGY, SECONDLY REDUCES THE OPERATIONAL ENERGY DEMAND AND LASTLY BUT NOT THE LEAST IMPROVES THE THERMAL COMFORT HENCE THE USER SATISFACTION. THE FOLLOWING BIOCLIMATIC DESIGN GUIDELINES HAS BEEN FORMULATED ON THE BASIS OF RESULTS FROM CLIMATE ANALYSIS AND THE STUDY OF VERNACULAR ARCHITECTURE OF THE LUCKNOW CITY. ORIENTATION RESULTS FROM BIOCLIMATIC, PSYCHOMETRIC CHART AND DEGREE DAYS SUGGEST THE REDUCTION OF HEAT GAIN INSIDE THE BUILDING. FOR THAT REASON ORIENTATION SHOULD BE IN NORTH SOUTH DIRECTION (EAST-WEST AXIS) THAT IS ALSO RECOMMENDED BY MAHONEY'S TABLE, AS HIGH ALTITUDE SUN CAN BE EASILY CUT BY SMALL OVERHANG AND LOW ALTITUDE SUN CAN BE ALLOWED TO ENTER B. LAYOUT COMPACT PLANNING OR SINGLY BANKED ROOMS AROUND MEDIUM SIZED COURTYARD IS RECOMMENDED BY MAHONEY'S TABLE MOREOVER VERNACULAR ARCHITECTURE OF LUCKNOW ALSO EDUCATE THE SAME. COMPACT PLANNING WITH USE OF SHARED WALLS, HEAT TRANSFER INTO THE INTERIORS CAN BE MINIMISED DUE LOW SURFACE AREA TO VOLUME RATIO. COURTYARD WITH SINGLY BANKED ROOMS FACILITATES THE VENTILATION AS WELL AS SHADES THE WINDOWS OPENING TOWARDS COURT. MOREOVER, IT PROVIDES THE OPEN SPACE IN THE INTERIOR THAT CAN UTILISED FOR SEATING AT EVENING IN SUMMERS AND AT DAYTIME IN WINTERS.

13. C. OPENINGS WINDOW TO WALL RATIO RECOMMENDED BY MAHONEY'S TABLE IS 15-20% TO MINIMISE HEAT GAIN WITH ADEQUATE DAYLIGHT INSIDE THE BUILDING. FROM SUN PATH DIAGRAM IT IS VISIBLE THAT SUN RAYS ARE AT ALMOST 90 DEGREE IN THE EAST AND WEST DIRECTION HENCE VERY DIFFICULT TO SHADE, THEREFORE MAXIMUM OPENINGS SHOULD BE IN NORTH AND SOUTH DIRECTION. SHADING OF WINDOW BIOCLIMATIC AND PSYCHOMETRIC CHART SUGGEST SHADING OF WINDOWS IN THE MONTHS FROM MARCH TILL OCTOBER. CONSEQUENTLY SHADING MASK CAN BE CREATED ON SUN PATH DIAGRAM ON THE MONTHS TO BE SHADED IN DIFFERENT DIRECTIONS. E. PASSIVE SOLAR HEATING BIOCLIMATIC AND PSYCHOMETRIC CHART ADVISE PASSIVE SOLAR HEATING IN THE MONTHS OF JANUARY, FEBRUARY, NOVEMBER AND DECEMBER. THIS CAN BE DONE EFFORTLESSLY BY PROVIDING WINDOWS IN THE SOUTH DIRECTION WITH OPTIMUM SHADE TO CUT SUMMER SUN AND ALLOW WINTER SUN. F. VENTILATION RESULTS FROM A ABOVE CLIMATE ANALYSIS RECOMMENDS VENTILATION IN THE MONTHS OF JUNE, JULY, AUGUST AND SEPTEMBER WHICH HAVE HIGH TEMPERATURE, HUMIDITY AND RECEIVES 80% OF THE TOTAL YEARLY RAINFALL. AIR MOVEMENT FACILITATES THE EVAPORATION OF SWEAT IN THIS HUMID WEATHER AND THUS CREATES THE COOLING SENSATION IN THE HUMAN BODY