weather hazards

indroductory agro- meterology and cimate change (agricultural (b.sc)

1. MALLA REDDY UNIVERSITY school of agricultur al sciences

2. INTRODUCTORY AGRO-METEROLOGY AND CLIMATE CHANGE Weather hazards

3. 2011AG010209-NALLURI BHUVAN 2011AG010210- NALLAGONI SAI DEEKSHITH 2011AG010211-G.L.S.VARSHA 2011AG010212-NARJALA DILSHAD KUMAR 2011AG010213-NAGOTHU DIVYA JYOTHI 2011AG010214-NEELI PARAMESWARI 2011AG010215-NEVURI PRAVALIKA 2011AG010216-DUMALA MEGANA

4. What is a weather hazard? Weather hazards are conditions which are unfavorable to people and their activities that result from weather phenomena. There are many types of Weather Hazards and most cannot be prevented although their effects can be mitigated.

5. Weather hazards Include hurricanes,  tornadoes, Thunder storms, lightning,  hail, winds, and winter weather. Many of these phenomena are related to atmospheric conditions that can be monitored and forecast.

6. DROUGHT A drought is a period of time when an area or region experiences below-normal precipitation. The lack of adequate precipitation, either rain or snow, can cause reduced soil moisture or groundwater, diminished stream flow, crop damage, and a general water shortage

7. Drought affect food production and human society, so they are considered a disaster, of natural, supernatural or human cause. A drought can last for months or years, or may be declared after as few as 15 days.

8. Drought in India  has resulted in tens of millions of deaths over the 18th, 19th, and 20th centuries. INDIAN agriculture is heavily dependent on the country’s climate a favorable southwest summer monsoon is critical to securing water for irrigating India's crops.

9. Drought is a recurring feature of the climate in most parts of the world. In fact studies based on dendrochronology, or tree rings dating, confirm that drought affected by global warming goes back to 1900.

10. Failure to develop adequate drought mitigation strategies carries a grave human cost in the modern era, exacerbated by ever-increasing population densities. President Roosevelt on April 27, 1935, signed documents creating the Soil Conservation Service now the Natural Resources Conservation Service . Models of the law were sent to each state where they were enacted.

11. Agriculturally, people can effectively mitigate much of the impact of drought through irrigation and crop rotation. The three longest drought episodes occurred between July 1928 and May 1942 July 1949 and September 1957 and June 1998 and December 2014

12. In India  in  recent  years, flash droughts occurred in 1986, 2001 and 2015. The 2001 flash drought-affected north and central India while the 1986 and 2015 flash  droughts were more widespread, impacting crop production

13. Really hot temperatures can make a drought worse by causing moisture to evaporate from the soil. Just because a region is hot and dry doesn't necessarily mean it is going through a  drought.

14. FLOODS A flood is an overflow of water that submerges land that is usually dry. Floods  are often   caused by heavy rainfall, rapid snowmelt or a storm surge from a tropical cyclone or tsunami in coastal areas land that is usually dry.

15. The most commonly used tool to measure floods is the stilling well.

16. Floods are measured with the help of fixed measuring sites that are set up throughout the country; the National Weather Service gathers its data from these sources. These sites were established in locations with large populations or those with provisions that accentuate possibilities of flooding.

17. Drainage systems and the effective infrastructure design aid during heavy rains. They help the drainage of excess water into reservoirs in an easy way. But in cases of heavy rainfall, the systems stop working. Thus flood is caused.

18. Flooding may occur as an overflow of water from water bodies , such as a  river, lake, or ocean, in which the water overtops or breaks levees, resulting in some of that water escaping its usual boundaries, or it may occur due to an accumulation of rainwater on saturated ground in an areal flood

19. Floods in INDIA In October1943, Madras saw the worst flood to hit the city. Flood Occurred due to excessive rains that lasted for 6 days and overflowed Coovum and the Adyar river Damage caused to life and property was immense however estimate figure is unknown. the flood left thousands of people homeless

20. The 2019 Indian floods were a series of floods that affected over thirteen states in late July and early August 2019, due to excessive rains. At least 200 people died and about a million people were displaced.

21. On 11 August 1979 the Machchu-2  dam situated on the MACHCHHU river burst, thus flooding the town of MORBI in the RAJKOT district of Gujarat Exact figure of loss of lives is unknown, but it is estimated between 1800 and 2500 people.

22. In July 1993 flash floods killed 530 people across the seven to eight states of India The 1993 India floods was a deadliest flood caused by several days long heavy monsoon rains and severe weather that occurred in July 1993 across eight states in the north of the country.

23. Heavy rains across the state of Maharashtra, including large areas of the  metropolis  Mumbai which received 567 alone on 26 July 2005 killed at-least 1,094 people. The day is still remembered as the day  Mumbai came to a standstill , as the city faced worst ever rain.

24. June 2013 north Indian floods  Heavy rain due to a burst of cloud  caused severe floods and landslides on the North Indian states, mainly UTTARAKHAND and nearby states. More than 5,700 people were presumed dead.

25. August 2018 KERLA flood Following high rain in late August 2018 and heavy monsoon rainfall from August 8, 2018, severe flooding affected the  India  state of KERLA resulting over 445 deaths 2020 Assam floods

26. FROST Frost is a thin layer of ice on a solid surface, which forms from water vapor in an above-freezing atmosphere coming in contact with a solid surface whose temperature is below freezing, and resulting in a phase change from water vapor to ice as the water vapor reaches the freezing point.

27. Frost is the coating or deposit of ice that may form in humid air in cold conditions, usually overnight. In temperate climates, it most commonly appears as fragile white crystals or frozen dew drops near the ground, but in cold climates, it occurs in a greater variety of forms.

28. Frost occurs on clear nights in early spring when the air temperature drops to 2°C or less. Crop damage from frost may occur at any stage of development but is most damaging at or around flowering.

29. Cereal grains will  lose leaf tissue that freezes. New growth will follow at the growing point which is protected below ground, prior to jointing. In some cases, the eventual maturity date may be delayed. 

30. Frost is water vapor, or water in gas form, that becomes solid.  Frost usually forms on objects like cars, windows, and plants that are outside in air that is saturated, or filled, with moisture.

31. The most typical  example of  deposition would be frost. Frost is the deposition of water vapour from humid air or air containing water vapour on to a solid surface. Solid frost is formed when a surface, for example a leaf, is at a temperature lower than the freezing point of water and the surrounding air is humid.

32. The temperature has to get down to 28 degrees F for a complete  kill on corn and soybean plants . Temperatures above 28 degrees F don't  kill the entire plant, but will damage the leaves and the upper stem.

33. The damage occurs when ice crystals form within  plant  tissue, damaging their cells. Leaves and tender new growth are usually affected first. Initially, they will appear wilted. Then the wilted growth will turn brown or black and eventually become crispy.

34. Tropical cycolone A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds , and a spiral arrangement of thunderstorms that produce heavy rain and/or squalls.

35. The strong rotating winds of a tropical cyclone are a result of the  conservation of angular momentum   imparted by the  Earth’s rotation as air flows inwards toward the axis of rotation. As a result, they rarely form within 5° of the equator.

36. Cyclones in coastal areas severely affect  all these components of agriculture sector through direct damage by high speed wind, torrential rain and extensive flooding. High tide may bring in saline water and sand mass making the fields unsuitable for agriculture.

37. As far as  agricultural impact  is concerned,  tropical storms can destroy standing crops and food stores , kill or injure livestock, damage homes and deplete the asset base of rural families .

38. On average around 2 to 4 tropical  cyclones impact India every year, while most of these tropical cyclones impact the east coast of Indian states of West Bengal, Odisha, Andhra Pradesh, Tamil Nadu.

39. Cyclones, storms and floods  can result in loss of harvest or livestock , increased susceptibility of livestock to disease, contamination of water bodies, land degradation through wind and water erosion and destruction of agricultural infrastructure such as roads and fences.

40. Farmers coped with the  cyclone by replanting  crop fields , rebuilding homes with local materials , reducing consumption of staple foods, harvesting wild foods and finding temporary work to buy food.