Natural Disasters - Earthquake & Cyclone

Natural disasters are catastrophic events caused by natural processes of the Earth. These disasters can lead to significant destruction, loss of life, and economic damage, affecting millions of people worldwide. They occur due to various environmental factors such as geological movements, climatic changes, and oceanic disturbances. Some of the most common types of natural disasters include earthquakes, tsunamis, hurricanes, floods, volcanic eruptions, landslides, droughts, and wildfires.
In this presentation we are going to study on two common powerful natural disasters Earthquake & Cyclone.

1. EARTHQUAKE & CYCLONE

2. Table of contents Definition Types Causes Impact on Ecosystems Mitigation & Preparedness 01 04 02 05 03 INTRODUCTION CYCLONE CONCLUSION EARTHQUAKE Definition Types Causes Impact on Ecosystems Mitigation & Preparedness REFERENCES

3. INTRODUCTION Natural disasters are catastrophic events caused by natural processes of the Earth. These disasters can lead to significant destruction, loss of life, and economic damage, affecting millions of people worldwide. They occur due to various environmental factors such as geological movements, climatic changes, and oceanic disturbances. Some of the most common types of natural disasters include earthquakes, tsunamis, cyclones, floods, volcanic eruptions, landslides, droughts, and wildfires. Natural disasters can be classified into different categories based on their causes: Geological Disasters – These include earthquakes, tsunamis, volcanic eruptions, and landslides, which occur due to movements within the Earth's crust. Hydrological Disasters – These involve water-related events such as floods, tsunamis, and storm surges. Meteorological Disasters – These result from extreme weather conditions like hurricanes, cyclones, tornadoes, and heatwaves. Climatological Disasters – These include droughts, wildfires, and extreme temperature fluctuations. Biological Disasters – These involve disease outbreaks, pest infestations, and pandemics.

4. EARTHQUAKE Definition An earthquake is the sudden shaking or vibration of the Earth's surface caused by the movement of rocks beneath the Earth's crust. This movement releases energy in the form of seismic waves, which travel through the Earth, causing the ground to shake. The severity of an earthquake is measured using magnitude scales (such as the Richter Scale or Moment Magnitude Scale) and its impact is measured by intensity scales (such as the Modified Mercalli Scale). TYPES TECTONIC EARTHQUAKES - C aused by plate movements. VOLCANIC EARTHQUAKES - Triggered by volcanic eruptions. EXPLOSION EARTHQUAKES - Caused by nuclear or chemical explosions. COLLAPSE EARTHQUAKES - Due to cave-ions or landslides. .

5. CAUSES OF EARTHQUAKE TECTONIC PLATE MOVEMENTS The Earth's crust is divided into large sections called tectonic plates. These plates constantly move due to convection currents in the mantle. When they interact, stress builds up and is eventually released as an earthquake. VOLCANIC ACTIVITY Earthquakes often occur near active volcanoes due to the movement of magma beneath the Earth's surface. These volcanic earthquakes can happen before, during, or after an eruption, as pressure builds up and is released violently. HUMAN – INDUCED (ANTHROPOGENIC) EARTHQUAKES Certain human activities can trigger earthquakes, including: Mining & Quarrying, Geothermal & Oil Extraction, Nuclear Explosions. FAULT SLIPPAGE (ELASTIC REBOUND THEORY) Over time, stress builds up along a fault line. When the accumulated stress exceeds the strength of the rocks, they break suddenly and shift, causing an earthquake. This process is known as the elastic rebound theory. LANDSLIDES & ROCKFALLS Sudden movements of large rock masses due to gravity can trigger minor earthquakes, especially in mountainous or unstable areas .

6. IMPACT ON ECOSYSTEMS Earthquakes have a significant impact on ecosystems, affecting landforms, water bodies, plant and animal life, and even the atmosphere. IMPACT ON LANDFORMS & SOIL Ground deformation & land subsidence Soil liquefaction Landslides & erosion Impact on water bodies & aquatic ecosystems Tsunamis & coastal flooding Change in river flow and lakes Mass mortality of marine animals Groundwater changes Impact on forests & Plant life F orest destruction Uproot trees Damage root systems Loss of agricultural land IMPACT ON WILDLIFE & ANIMAL POPULATIONS Displacement & habitat loss Animal casualties (injuries or deaths) Changes in predator-prey relationships IMPACT ON ATMOSPHERIC & CLIMATE CONDITIONS Release of greenhouse gases from underground reservoirs Climate change Air and dust pollution

7. Mitigation strategies & preparedness Earthquake-resistant buildings - Use reinforced concrete, steel frames, and flexible foundations. Shock absorbers - Absorb seismic waves to reduce shaking. Cross-branching & Shear walls - strengthen buildings to withstand earthquakes. Retrofitting Old Structures - Strengthen weak buildings with modern materials. Seismic resistant infrastructure - Bridges, highways, and dams designed to handle earthquakes. Secure heavy furniture & appliances - Prevent falling objects. Urban planning - Avoid building in high-risk areas. Create an emergency plan - Set evacuation routes. Prepare an emergency kit - Water, food, flashlight, first aid. Early warning systems - Seismographs, mobile alerts, sirens, gas line shutdowns. Disaster response teams - Provide emergency services during disaster.

8. cyclone definition A cyclone is a large-scale air mass that rotates around a strong center of low atmospheric pressure. It is characterized by strong winds, heavy rainfall, and storm surges, often leading to widespread destruction. Cyclones occur over warm ocean waters and can travel great distances, affecting coastal and inland areas. The intensity of cyclones is measured using the Saffir-Simpson Hurricane Scale or the Beaufort Wind Scale. types Tropical Cyclones (Most Destructive) Form over warm ocean waters near the equator. Cause heavy rainfall, strong winds, and storm surges. Examples: Hurricane Katrina (2005), Typhoon Haiyan (2013). Extratropical Cyclones Develop outside the tropics, between 30° and 60° latitude. Associated with cold and warm fronts, bringing heavy rain and snow. Example: The "Bomb Cyclone" in the US (2022). Subtropical Cyclones Hybrid storms with features of both tropical and extratropical cyclones. Less intense but still cause strong winds and heavy rain. . .

9. Causes of cyclone Cyclones form due to a combination of oceanic and atmospheric conditions. The main causes include: Warm Ocean Waters (Above 26°C/79°F) Warm sea surface temperatures provide the energy and moisture needed for cyclone formation. The heat causes evaporation, leading to the formation of strong clouds and storms. Low Atmospheric Pressure A low-pressure system allows warm, moist air to rise rapidly. As the air rises, it cools and condenses, forming thunderstorms and intensifying the system. Coriolis Effect (Earth’s Rotation) The Earth's rotation causes the air to spin counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. This rotation helps organize the storm into a circular motion. High Humidity in the Troposphere High levels of moisture in the atmosphere fuel cloud formation and storm intensification. Weak Wind Shear Wind shear refers to the change in wind speed and direction with height. Low wind shear allows a cyclone to grow vertically and maintain its structure.

10. IMPACT ON ECOSYSTEMS Cyclones have a devasting impact on ecosystems, affecting land, water, plant life, and animal populations. Impact on Land and Soil Soil erosion Landslides Saltwater intrusion Destruction of natural landforms. Impact on Water Bodies and Marine Life Cyclone contaminates freshwater sources (lakes, rivers) with debris and pollutants. Fish population decline due to strong currents & temperature changes. Coral reef destruction. Impact on Forests and Vegetation Deforestation Habitat loss - Many plants species die due to excessive flooding. Delayed plant regeneration Impact on Wildlife and Animal populations Displacement of animals (Due to cyclone, wildlife has to migrate) Mass mortality - Birds, insects, and small mammals are unable to survive strong winds and heavy rains. Loss of nesting and breeding grounds. Food chain disruption. Impact on Atmospheric & Climate conditions Greenhouse gas emissions - Cyclones uproot forests, reducing carbon absorption. Alteration of local weather patterns - Long-term climate changes due to disrupted ocean currents. Dust and Debris pollution - Strong winds carry pollutants and increase respiratory health risks.

11. Mitigation strategies & preparedness Cyclone-resistant buildings - Use reinforced materials, sloped roofs, and strong foundations. Elevated structures - Houses and critical infrastructure raised to prevent flood damage. Seawalls and embankments - Protect coastal areas from storm surges. Zoning laws - Restrict construction in high risk cyclone prone areas. Early warning systems - Advanced forecasting and alerts to warn communities. Disaster management policies - Government plans for response. Public awareness campaigns - Educating communities on cyclone. Create an emergency kit - Food, water, medicine, flashlight, first aid supplies. Evacuation shelters - Pre- identified safe locations with basic supplies. Secure property - The down loose objects, reinforce doors and windows. Rescue and medical teams - Trained personnel for emergency.

12. conclusion Natural disasters are unpredictable and destructive events. Earthquakes and cyclones are powerful natural disasters that cause widespread destruction to lives, property, and the environment. While earthquakes result from tectonic movements, cyclones develop due to atmospheric, and oceanic conditions. Both disasters lead to loss of life, economic damage, and long-term environmental consequences. Effective mitigation and preparedness. strategies are essential in minimizing their impact. Governments, scientists, engineers, and communities must collaborate to improve disaster resilience.

13. references https://en.wikipedia.org/wiki/Natural_disaster https://www.sciencedirect.com/topics/earth-and-planetary-sciences/natural-disaster https://www.britannica.com/science/natural-disaster https://www.planetaryhealthalliance.org/natural-disasters https://pubmed.ncbi.nlm.nih.gov/31445607/#:~:text=Abstract,stresses%20an%20already%20occupied%20facility

14. THANK YOU BY – SIMRAN ASWANI 24MSBT49