Typhoon Shanshan
Why in News: Typhoon Shanshan has strengthened into a “very strong” storm as it nears Japan’s southwestern coast, leading weather agencies to issue warnings.
About Tropical Cyclone:
Formation:
- Origin: Tropical cyclones develop over warm ocean waters near the equator, where warm, moist air rises from the ocean surface, creating a low-pressure area.
- Air Movement: Higher-pressure air from surrounding areas moves toward the low-pressure zone, causing the air to warm and rise further. This rising air cools, forming clouds.
- Intensification: The system of spinning clouds and wind strengthens with the ocean’s heat. As wind speeds increase, a central eye forms.
Characteristics of a Tropical Cyclone:
- Calm Centre: The cyclone’s centre, or eye, is typically calm and clear with very low air pressure.
- Wind Speed: Average wind speeds are around 120 km/h.
- Closed Isobars: These cyclones feature closed isobars, leading to high wind velocities.
- Oceanic Origin: They form exclusively over oceans and seas.
- Movement: Tropical cyclones typically move from east to west, are influenced by trade winds, and have seasonal patterns.
Classification of Cyclones:
Categories: The Indian Meteorological Department (IMD) classifies cyclones based on wind speeds:
- Depression: Wind speeds between 31–49 km/h.
- Deep Depression: Wind speeds between 50–61 km/h.
- Cyclonic Storm: Wind speeds between 62–88 km/h.
- Severe Cyclonic Storm: Wind speeds between 89–117 km/h.
- Very Severe Cyclonic Storm: Wind speeds between 118–166 km/h.
- Extremely Severe Cyclonic Storm: Wind speeds between 167–221 km/h.
- Super Cyclonic Storm: Wind speeds above 222 km/h.
Naming of Tropical Cyclones:
Naming Authorities: Tropical cyclones are named by one of five regional bodies:
- ESCAP/WMO Typhoon Committee
- WMO/ESCAP Panel on Tropical Cyclones
- RA I Tropical Cyclone Committee
- RA IV Hurricane Committee
- RA V Tropical Cyclone Committee
Indian Ocean: The WMO/ESCAP Panel on Tropical Cyclones is responsible for naming cyclones in the Indian Ocean.
Northern bald ibis
Why in News: Since 2002, biologist Johannes Fritz and the Waldrappteam have successfully increased the northern bald ibis population in Central Europe from zero to nearly 300, shifting its status from “critically endangered” to “endangered.”
About Northern Bald Ibis:
- Scientific Name: Geronticus eremita
- Conservation Status: Endangered (previously Critically Endangered)
- Historical Range: Once native to Central Europe until the 17th century; also found in North Africa and the Arabian Peninsula.
- Extinction in Europe: Became extinct in Central Europe by the 17th century due to overhunting.
Distinctive Features:
- The Northern Bald Ibis has black plumage with an iridescent green sheen, a bald red head with black markings, and a long, downward-curved beak.
- Their red beak and legs contrast with their dark feathers.
- No sexual dimorphism is present in this species.
Diet:
- Primarily feeds on insect larvae, earthworms, and other invertebrates, using their long, slender beak to probe the ground, guided by their sense of touch.
Habitat:
- Prefers open areas with short grass, such as meadows, pastures, or even sports fields like golf courses.
- Despite their vulture-like bald head, they are not scavengers.
Social Behaviour:
- Social birds that historically formed large colonies with thousands of individuals.
- Engage in a ritual greeting involving crest-spreading and bowing, which often triggers similar responses throughout the colony.
Monogamy:
- Typically seasonally monogamous, with breeding partnerships often changing yearly, though some pairs may stay together for multiple years.
Breeding Habits:
- Choose steep rock faces with protective nooks for nesting, laying up to four greenish eggs.
- Incubation starts with the first egg, leading to staggered hatching times.
Nestling Development:
- Young birds fledge within 42-50 days, initially following their parents before joining juvenile groups.
- Learn migration routes by following experienced birds during the fall migration.
Talley Valley Wildlife Sanctuary
Why in News: A lepidopterist from Mumbai recently documented 85 butterfly species during a four-day expedition at the Tale Wildlife Sanctuary in Arunachal Pradesh’s Lower Subansiri district.
About Talley Valley Wildlife Sanctuary:
Location: Situated in the Lower Subansiri district of Arunachal Pradesh.
Geography:
- The sanctuary is a plateau, covering an area of 337 sq. km.
- It is located at an altitude of 2400 meters, with rivers like Pange, Sipu, Karing, and Subansiri flowing through it.
Cultural Significance: Inhabited by the Apatani tribe, known for their distinct customs, traditions, and handicrafts.
Flora:
- Boasts a diverse range of subtropical and alpine forests, including silver fir trees, ferns, orchids, bamboo, and rhododendrons.
- Home to Pleioblastus simone, a unique bamboo species found only in Talley Valley.
- Rich in medicinal plants and herbs utilized by local tribes for traditional medicine.
Fauna:
- Hosts a variety of animal species such as elephants, barking deer, giant squirrels, porcupines, leopards, clouded leopards, wild boars, and more.