Hurricane Milton made landfall near Siesta Key, Florida, USA which caused heavy rain, flooding and strong winds resulting in significant damage and loss of lives.
Hurricane Milton: Origin and Causes
Hurricane Milton was a powerful storm that made landfall in Florida near Siesta Key, causing widespread damage.
It was a Category 5 hurricane with wind speeds of 285 km/h, making it one of the strongest hurricanes ever recorded in the Atlantic Ocean.
It originated in the Gulf of Mexico, an area connected to the Atlantic Ocean.
Why it was an unusual storm?
Milton went from a Category 1 storm to a Category 5 storm in just 12 hours.
Usually, hurricanes intensify at a slower pace, but Milton’s wind speeds increased by 145 km/hin one day, which is very rare.
Sea-surface temperatures of 31°C were much higher than the 26°C needed for hurricane formation.
This excess heat allowed Milton to intensify quickly.
Most hurricanes follow a westward path, but Milton moved eastward and made landfall on the western coast of Florida.
According to scientists, very few hurricanes have taken this path before.
Wind shear is a change in wind speed and direction that can weaken hurricanes.
In Milton’s case, there was almost no wind shear, allowing the storm to grow stronger without interference.
PYQ:
[2020] Consider the following statements:
1. Jet streams occur in the Northern Hemisphere only.
2. Only some cyclones develop an eye.
3. The temperature inside the eye of a cyclone is nearly 10ºC lesser than that of the surroundings.
Which of the statements given above is/are correct?
Q). Discuss about the vulnerability of India to earthquake-related hazards. Give examples including the salient features of major disasters caused by earthquakes in different parts of India during the last three decades. (UPSC CSE 2021) Q). Describe the various causes and the effects of landslides. Mention the important components of the National Landslide Risk Management Strategy. (UPSC CSE 2021) Q). Discuss the recent measures initiated in disaster management by the Government of India departing from the earlier reactive approach. (UPSC CSE 2020) Q). Disaster preparedness is the first step in any disaster management process. Explain how hazard zonation mapping will help disaster mitigation in the case of landslides. (UPSC CSE 2019)
Prelims:
The 2004 Tsunami made people realize that mangroves can serve as a reliable safety hedge against coastal calamities. How do mangroves function as a safety hedge? (UPSC CSE 2011) a) The mangrove swamps separate the human settlements from the sea by a wide zone in which people neither live nor venture out b) The mangroves provide both food and medicines which people are in need of after any natural disaster c) The mangrove trees are tall with dense canopies and serve as an excellent shelter during a cyclone or tsunami d) The mangrove trees do not get uprooted by storms and tides because of their extensive roots.
Mentor’s Comment: Today’s editorial discusses the limitations in our present governance and management concerning Natural Disasters. The recent landslide event in Kerala is considered one of the deadliest landslides in India’s history, raising urgent concerns about the effectiveness of disaster management strategies in the region, which has a history of similar incidents over the past four decades. Previously, we saw the limitations based on the Disaster Management Act. Now, this article will help you to build a better consensus around the same theme.
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Let’s learn!
Why in the News?
On July 30, 2024, the Wayanad district in Kerala experienced devastating landslides that resulted in significant loss of life and property.
The Chief Minister (Kerala) emphasized the need for a reevaluation of disaster preparedness and response approaches, highlighting the helplessness against natural calamities across the state.
Kerala is no longer relatively disaster-free:
The state of Kerala which is bordered by the Arabian Sea and Western Ghats, was once viewed as disaster-free, which influenced its development patterns.
The frequency and intensity of disasters have surged in recent decades. Over 250 km of Kerala’s coastline is affected by erosion.
Further, the high population density in the Western Ghats exceeded its vulnerability to disasters.
Lowlands like Vembanad Lake, frequently experience flooding during monsoons.
The 2018 floods were labeled the “floods of the century” by the World Meteorological Organization.
Infrastructure development has often ignored natural drainage and slope stability, leading to increased disaster risks.
Why a Comprehensive inventory mapping is needed?
Physical Geography of the Region: Tectonic activity generally correlates with landslide occurrences.
For example, the Wayanad region is characterized by deep gorges and ravines, which is prone to landslides.
Climate Change Impact: Rapid warming of the Arabian Sea increases risks of extreme weather events like floods and cyclones. For example, the Cyclone Ockhi in 2017.
Research Gaps: Current understanding of landslide causative factors is limited; a nuanced approach is necessary for effective disaster mitigation.
Monitoring Mechanisms: Establishing monitoring systems for rainfall and tremors can provide timely warnings to prevent loss of life.
Shrinking Safe Space: The “safe operating space” for communities in Kerala is diminishing due to increasing natural disasters.
Need for a Paradigm Shift (Way Forward):
Need to work on Disaster Risk Zones: Develop disaster risk zones based on physical and social criteria within a social-ecological framework, aligned with watershed boundaries.
Strengthening the disaster risk governance and invest them in risk reduction to enhance resilience and preparedness would be helpful.
Comprehensive Approach: Emphasize all aspects of the disaster cycle: preparedness, resilience, risk reduction, mitigation, reconstruction, recovery, response, and relief.
The Sendai’s global framework highlights the State’s primary role in disaster risk reduction while advocating for shared responsibility with local governments, private sectors, and communities.
Quadruple Helix Model: Utilize a collaborative model involving community organizations, academia, government, and industry for effective disaster risk management.
Engage communities in creating disaster risk maps through a community-based disaster risk management approach.
An annular solar eclipse will be visible in parts of South America on October 2, 2023. It, however, will not be visible from India.
What is a Solar Eclipse?
A solar eclipse occurs when the Moon moves between the Earth and the Sun, blocking the Sun’s light either fully or partially, casting a shadow on certain parts of the Earth.
There are four types of solar eclipses:
Total Solar Eclipse: When the Moon completely blocks the Sun, turning the sky dark. People in the path of a total solar eclipse can witness the Sun’s corona (its outer atmosphere), which is normally hidden by the bright sunlight.
Annular Solar Eclipse: Occurs when the Moon is at or near its farthest point from Earth. The Moon does not fully cover the Sun, leaving a visible ring of fire around the Moon. This is what people in parts of South America will witness on October 2, 2023.
Partial Solar Eclipse: Happens when the Moon blocks only a part of the Sun, giving it a crescent shape. During both partial and annular eclipses, areas outside the Moon’s umbra (the darkest part of its shadow) experience a partial eclipse. It is the most common type of solar eclipse.
Hybrid Solar Eclipse: The rarest type, where the eclipse shifts between total and annular as the Moon’s shadow moves across the Earth. Some places see a total solar eclipse, while others see an annular one.
Frequency of Solar Eclipses
A solar eclipse can only occur during the new moon, when the Moon and Sun are aligned on the same side of the Earth.
A new moon happens approximately every 29.5 days because that is the time it takes for the Moon to orbit the Earth.
However, solar eclipses don’t happen every month. They occur two to five times annually, but not every new moon results in an eclipse.
Why don’t they occur every month:
The Moon’s orbit around the Earth is tilted by about 5 degrees compared to the Earth’s orbit around the Sun.
This means the Moon’s shadow usually misses the Earth.
A solar eclipse only occur when the Moon crosses specific points in its orbit, called nodes, where the Moon’s orbit intersects the plane of Earth’s orbit around the Sun.
When a new moon occurs at one of these nodes, a solar eclipse is possible.
PYQ:
[2019] On 21st June, the Sun
(a) does not set below the horizon at the Arctic Circle
(b) does not set below the horizon at Antarctic Circle
(c) shines vertically overhead at noon on the Equator
(d) shines vertically overhead at the Tropic of Capricorn
In September 2023, seismic stations across the world detected an unusual signal which persisted for 9 days.
It was caused by a massive landslide in Greenland’s Dickson Fjord (i.e narrow sea inlet with steep sides or cliffs, created by a glacier).
About the Massive Greenland Landslide
The landslide involved a colossal volume of 25 million cubic metres of rock and ice, equivalent to filling 10,000 Olympic-sized swimming pools.
The landslide involved 25 million cubic meters of rock and ice, which is enough to fill 10,000 Olympic-sized swimming pools.
This event caused a mega-tsunami with waves as high as 200 meters, which significantly impacted the area.
The seismic waves created by the landslide lasted for 9 consecutive days.
The loss of such a large amount of glacier ice highlights how global warming is speeding up damage to these fragile environments.
Causes of the Greenland Landslide
The main reason for the landslide was global warming, which caused the glaciers in Greenland to melt and shrink over recent decades.
The Hvide Stovhorn peak glacier had been holding up the mountain slopes, but as it thinned, the rock above it became unstable and eventually collapsed.
The permafrost (frozen ground) on the mountain’s steep slopes started melting because of rising temperatures, making the slopes unstable.
When the rocks and ice fell into the fjord, it triggered a submarine landslide (a landslide under water), which made the event even bigger and caused a mega-tsunami.
In a rare celestial event, Earth’s gravitational field will witness a small asteroid, 2024 PT5, creating a “mini-moon” for two months.
What is Mini-Moon?
A mini-moon is a small asteroid temporarily captured by Earth’s gravitational field, orbiting the planet for a short period before escaping back into space.
Unlike Earth’s permanent moon, mini-moons only stay for a few monthsto a few years before being ejected from orbit.
Mini-moons are a rare occurrence because most asteroids either pass by Earth or burn up in the atmosphere rather than being captured by Earth’s gravity.
Mini-moons are usually small, often just a few meters in diameter.
For example, 2024 PT5 is only about 33 feet (10 meters) in length.
They are hard to detect and are usually discovered using advanced telescopicsurveys like NASA’s Asteroid Terrestrial-impact Last Alert System (ATLAS).
Significance of Mini-Moons
Mini-moons offer scientists a unique opportunity to study near-Earth objects, enhancing our understanding of asteroids’ behavior and composition.
Mini-moons could contain valuable minerals or water, making them potential targets for future space missions to extract resources.
Studying mini-moons helps scientists learn more about Earth’s gravitational influence and how it interacts with space objects.
PYQ:
[2011] What is the difference between asteroids and comets?
Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material.
Asteroids are found mostly between the orbits of Jupiter and Mars, while comets are found mostly between Venus and Mercury.
Comets show a perceptible glowing tail, while asteroids do not.
Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 1 and 3 only
(c) 3 only
(d) 1, 2 and 3
The Volcanic Island of Rapa Nui (also known as Easter Island) has always been mysterious due to its harsh geography and iconic Moai statues.
About Rapa Nui Island
Details
Location
• Situated in the southeastern Pacific Ocean, Rapa Nui is part of Polynesia and a territory of Chile.
• One of the most remote islands, about 3,500 km from Chile.
Size
• Covers an area of 160 sq. km.
Geographical details
• The island has a volcanic origin, featuring lava-covered terrain and rocky soil.
• Notable volcanoes include Terevaka, Poike, and Rano Kau.
• Tropical climate with average temperatures ranging between 18°C and 28°C.
• Rainfall occurs mostly in the winter months.
Moai Statues
• Famous for over 900 moai statues, some as tall as 40 ft and weighing 75 tonnes.
• These statues were built between the 13th and 16th centuries to honor revered ancestors.
• Carved from volcanic rock and transported across great distances.
Discovery
• Discovered by European sailors on Easter Sunday, 1722, which gave it the name Easter Island.
• The island had been settled centuries earlier by Polynesian explorers who navigated thousands of kilometers of ocean.
Significance of New Findings
• Recent studies, including the use of AI analysis of satellite images, have debunked earlier theories of ecological collapse.
• Genetic studies show Native American ancestry before European contact, indicating earlier interactions with South America.
PYQ:
[2018] Consider the following statements:
1. The Barren Island volcano is an active volcano located in the Indian territory.
2. Barren Island lies about 140 km east of Great Nicobar.
3. The last time the Barren Island volcano erupted was in 1991 and it has remained inactive since then.
Which of the statements given above is/are correct?
India has launched Operation Sadbhav to provide humanitarian assistance to Southeast Asian countries affected by Typhoon Yagi, including Vietnam, Laos and Myanmar.
Typhoon Yagi: Origin and Impact
Typhoon Yagi began as a tropical storm in the western Philippine Sea on September 1, 2024.
Yagi, which means goat or the constellation ofCapricornus in Japanese.
It made landfall in the Philippines but intensified again due to warm waters in the South China Sea, reaching Category 3 winds by September 4.
Yagi further strengthened to a Category 5 typhoon with peak winds of 260 kmph, making it one of only four Category 5 storms recorded in the South China Sea.
Although downgraded to a tropical depression, it continued to bring heavy rains and floods to Myanmar and other areas.
What areTyphoons?
A Typhoon is a type of tropical cyclone that forms in the northwestern part of the Pacific Ocean, particularly affecting East Asia, Southeast Asia, and parts of Oceania.
They are characterized by strong winds, heavy rain, and can cause severe flooding, storm surges, and damage to infrastructure.
Key Features of Typhoons:
Formation Region: Typhoons form in the Northwestern Pacific Ocean, primarily between 100°E and 180°E.
Wind Speed: To be classified as a typhoon, sustained winds must exceed 119 km/h.
Structure: Like hurricanes, typhoons have a central eye (calm area) surrounded by a violent eyewall where the strongest winds and heaviest rains occur.
Season: Typhoons typically occur from May to October, with a peak from August to September.
Global Terminology:
Typhoon: Northwest Pacific Ocean.
Hurricane: North Atlantic, Central and Eastern North Pacific Oceans.
Cyclone: South Pacific and Indian Ocean.
PYQ:
[2020] Consider the following statements:
1. Jet streams occur in the Northern Hemisphere only.
2. Only some cyclones develop an eye.
3. The temperature inside the eye of a cyclone is nearly 10ºC lesser than that of the surroundings.
Which of the statements given above is/are correct?
A rare August cyclone, named ‘Asna’, currently positioned off the Kutch coast is even more remarkable for having originated over land.
Why was there a lot of excitement over Asna?
“Asna” is notable because it’s the first cyclone in August in the North Indian Ocean since 1981. August is typically not part of the cyclone season in this region.
The cyclone began as a land-born depression that intensified as it moved over the warm waters of the Arabian Sea. It formed from a rare strong low-pressure system that grew unusually powerful over land.
Asna’s formation is linked to the broader context of rapid warming over the Arabian Sea, influenced by climate change. The northward shift of the low-level jet stream due to warming over West Asia contributed to its development.
Why does the North Indian Ocean have two cyclone seasons?
The North Indian Ocean has two distinct cyclone seasons due to the unique monsoonal circulation patterns in the region:
Pre-monsoon season (March-May): The Arabian Sea warms rapidly during this time as the sun crosses over to the Northern Hemisphere. The Bay of Bengal is relatively warmer and begins producing atmospheric convection and rainfall. This leads to cyclogenesis in both the Arabian Sea and the Bay of Bengal.
Post-monsoon season (October-December): This is the northeast monsoon season for India. The Arabian Sea cools due to the strong southwesterly winds and mixing of cold subsurface waters. However, the Bay of Bengal remains favourable for cyclogenesis. The post-monsoon season is the major cyclone season in the North Indian Ocean
How is climate change affecting the region?
Warming of the Indian Ocean: Climate change is amplifying the warming of the Indian Ocean, with more heat being transferred from the Pacific Ocean and Southern Ocean. This increases the overall sea surface temperature (SST), crucial for cyclone formation.
Monsoon and cyclones: The warming affects the monsoon patterns and has the potential to change cyclone intensity. More heat and moisture from the warming seas lead to more energy available for cyclones.
Impact on global ocean circulation: The warming of the Indian Ocean is also affecting global ocean currents, impacting heat uptake by the Pacific Ocean and water sinking in the North Atlantic. The Indian Ocean is playing a central role in global climate change processes.
Way forward:
Strengthening Early Warning Systems: Enhance real-time monitoring and forecasting of cyclones, particularly in the pre- and post-monsoon seasons, using satellite data and advanced models.
Building Climate Resilience: Implement climate adaptation strategies, especially for coastal communities, by improving infrastructure and disaster preparedness to cope with increasing cyclone intensity due to climate change.
Mains PYQ:
Q Discuss the meaning of colour-coded weather warnings for cyclone prone areas given by India Meteorological Department. (UPSC IAS/2022)
Researchers have been curious about why the majority of gold nuggets discovered throughout history have been found in orogenic quartz veins.
Location and distribution of Gold:
Orogenic gold systems are commonly found in mountainous regions where large-scale geological processes, such as the collision of tectonic plates, have occurred.
For example, the Himalayas, the Canadian Shield, and the Western Australian goldfields.
Large gold nuggets are often found in orogenic quartz veins formed during the tectonic processes that create mountains.
These nuggets form because, during earthquakes, the stress on quartz crystals causes a reaction that deposits gold on their surfaces. This process happens repeatedly, leading to the accumulation of gold nuggets.
Note:
Gold nuggets are naturally occurring pieces of gold that have formed into lumps or chunks. They are typically found in riverbeds, streams, or within rock formations, often in quartz veins.
Orogenic quartz veins are quartz veins that form in mountainous regions.
Findings by Researchers:
Piezocatalytic Effect and Gold Accumulation: Researchers discovered that the piezocatalytic effect of quartz under seismic stress causes the accumulation of gold in quartz veins.
The piezoelectric quartz crystal generates an electric field when subjected to stress.
This field can drive electrochemical reactions at the interface between the quartz and a surrounding aqueous solution containing dissolved gold. These reactions cause gold to be deposited on the quartz surface.
Seismic Activity and Localized Gold Deposits: The study suggests that gold nuggets in orogenic systems are formed through repeated piezocatalytic reactions over time, driven by natural seismic activity. This process explains the highly localized and interconnected nature of gold deposits within quartz veins.
Conclusion: Researchers have found that gold nuggets in orogenic quartz veins form through piezocatalytic reactions caused by seismic stress on quartz. This process drives gold deposition on quartz surfaces, explaining the concentration and localization of gold in mountainous regions.
Mains PYQ:
Q Craze for gold in Indian has led to surge in import of gold in recent years and put pressure on balance of payments and external value of rupee. In view of this, examine the merits of Gold Monetization scheme. (UPSC IAS/2015)
