The all-India wheat production is projedted at 110.65 million tonnes, slightly above the 109.63 million tonnes produced in 2024-25, after factoring in recent weather damage, The Agriwatch Annual Wheat Survey for 2025-26 has said. New Delhi: The Union Government has raised its wheat procurement
Mercedes-Benz CLA Electric has launched in India at Rs 55 lakh (ex-showroom) with up to 792 km range, 800V fast-charging tech, multiple variants and features to improve long-distance EV usability. The Mercedes-Benz India has launched the CLA Electric at Rs 55 lakh (ex-showroom)
Apple could be working on a quad-curved display for its 20th Edition iPhone that could debut in September next year. The phone could run on A21 Pro processor while packing an all-glass design While the iPhone 18 Pro lineup is just months away
Youtuber Salim Wastik arrested for 1995 kidnap-murder: How he was nabbed after 31 yearsThe case pertains of the kidnapping and murder of a 13-year-old son of a businessman in 1995. Updated on: Apr 25, 2026 5:05 PM IST Written by Majid Alam Share via Copy link A man wanted for a 1995 murder of a
Hyderabad-based Skyroot Aerospace has flagged off its Vikram-1 rocket for India's first privately built orbital mission, targeting a June launch. The 23-meter rocket, developed over four years, aims to validate performance and gather flight data
What does ‘visibility’ mean in weather science?
What does ‘visibility’ mean in weather science? Premium
A: In weather science, ‘visibility' is a colloquial term for a quantity called the meteorological optical range. It's defined as the distance a beam of light can travel through the atmosphere before its intensity drops to 5% of its original value.
In an older time, a human observer would stand at a point and look for predetermined landmark objects at known distances, e.g. a water tower at 1 km and a temple at 5 km. If the observer can clearly distinguish the object against the skyline, the visibility is at least that distance. At night, they used lights of known intensity.
Modern weather stations use sensors to measure the visibility. In the direction version, a transmitter shoots a laser beam at a receiver located a specific distance away (often 20-75 m). The receiver measures exactly how much light made it across. In the indirect version, a transmitter projects a beam of light past a receiver, not directly at it. If the air is clear, the receiver sees nothing; If there's fog or dust, the particles scatter the light, deflecting some into the receiver. The amount of scattered light is converted into a visibility distance.
The India Meteorological Department also classifies visibility depending on smog (i.e. smoke + fog) intensity. This scheme ranges from 500-1,000 m for ‘shallow fog' to less than 50 m for ‘very dense fog'. On January 18, the visibility in Delhi had dropped to ‘poor', i.e. 50-200 m.
Published - January 18, 2026 10:53 am IST
weather science / air pollution / Question Corner
Source: TheHindu
Related Posts: Budget 2026-27 signals shift to ‘long-term vision’ from ‘short-term support’ Chennai flights diverted as visibility drops to 150 metres Low visibility Dense Fog, Reduced Visibility Disrupt Flight Operations In Delhi Dense Fog, Low Visibility Hits Flight Ops Low visibility prevents PM’s helicopter from landing in Taherpur Dense Fog, Low Visibility Disrupts Flight Ops Across North, East India Dense Fog, Low Visibility Disrupt Flight Operations In Northern India Delhi-NCR Engulfed In Dense Smog With Almost Zero Visibility Red Alert In Delhi As Dense Fog Reduces Visibility
From Lahore to Asian Tour, Ahmad Baig flies solo for Pakistan golfPakistani golfer Ahmad Baig excels at the International Series in Singapore, overcoming challenges of isolation and logistics as he pursues his dream. Published on: Apr 25, 2026 3:56 PM IST By Shantanu Srivastava Share via Copy link
1 days ago
Sanjay Dutt’s fans were in for a treat as the Bollywood actor announced his new film, Khalnayak Returns, on Friday. The film offers a fresh take on the 1993 blockbuster ‘Khalnayak’ starring Dutt, Madhuri Dixit and Jackie Shroff in lead roles. Now, with the sequel announcement after 33 years
1 days ago
Union Finance Minister on Saturday urged all entities in the to be 'exceptionally vigilant' on .Without naming , the newly minted platform from leading AI company Anthropic, Sitharaman said artificial intelligence tools are making cyberattacks faster and more adaptive
1 days ago
BJP's ‘Sheesh Mahal’ jibe at Kejriwal isn't new. Here's how row 2.0 emergedWhile the AAP denied allegations and questioned the veracity of photos shared by BJP, it was Delhi minister Parvesh Verma who took the lead in the attack Updated on: Apr 25
1 days ago
First-word problems: What did the earliest writers write about?A new book explores ancient letters about kings, pleas for help from a bereft mother, classroom exercises and ancient doodles – all dating to before 1500 BCE. Published on: Apr 25
1 days ago
Salman Khan, who is preparing for Maatrubhumi, has confirmed that his collaboration with Dil Raju, SVC63, featuring Nayanthara, is set to release in 2027. This project signifies an important partnership with Telugu film producer Dil Raju and director Vamshi Paidipally
1 days ago
If you have been struggling to build a consistent, feel-good morning routine, Samantha Ruth Prabhu may have just shared the reset you need. The actor swears by a simple yet powerful 8-step morning routine that, when followed for 21 days, can help reduce inflammation, calm your nervous system
1 days ago
Former Bharat Rashtra Samithi leader K Kavitha on Saturday launched her party Telangana Rashtra Sena. The name of the new party echoes the former name of Bharath Rashtra Samithi, which was earlier called Telangana Rashtra Samithi. Kavitha’s announcement came months after she resigned from the
1 days ago
Rahul Gandhi addressed an election rally in Serampore. He stated Prime Minister Narendra Modi and West Bengal Chief Minister Mamata Banerjee both help the rich. Gandhi claimed Modi sells the country and spreads hatred. He contrasted this with Congress's ideology of unity and brotherhood
1 days ago
Deloitte will cut parental leave, PTO, pension accruals and IVF-related benefits for some US employees from 2027, as part of a broader restructuring and benefits overhaul. Deloitte is set to cut several employee benefits for a section of its US workforce starting January 1, 2027
1 days ago
Social activist Anna Hazare said the exit of Raghav Chadha and six other Aam Aadmi Party (AAP) Rajya Sabha MPs could have been avoided if the party had followed the “right” path. Speaking to reporters in Ahilyanagar district of Maharashtra, Hazare said
1 days ago
America has frozen 344 million dollars in cryptocurrency assets. These funds are linked to Iran. This action aims to increase pressure on Tehran. Energy supplies are disrupted due to the war in the Middle East. The Treasury Department vows to degrade Iran's ability to move funds
1 days ago
X’s standalone messaging app, XChat, was rolled out to the public on Friday. The app is currently available on iOS devices and lets users connect with their X contacts for messaging, file sharing, audio and video calls, and group chats.Taking to X, lead designer Benji Taylor said
1 days ago
Republicans are adjusting their strategy for upcoming midterm elections. They aim to use President Trump's ability to mobilize voters without making the elections about his unpopularity. The focus will shift to promoting tax cuts and inflation-fighting policies
1 days ago
‘I just want to go back’: Indian woman in Dublin says missing cousin’s wedding is real cost of living abroadAn Indian woman in Dublin said missing her cousin’s wedding in India showed the real emotional cost of living abroad. Updated on: Apr 25
1 days ago
In an alternate universe: How will the Mandela Effect evolve, in the age of AI?Long before software manipulation, people were ‘remembering’ things that hadn’t happened. Could studying how this works help us frame a way forward? Updated on: Apr 25
1 days ago
![New Delhi [India], April 25 (ANI): A fire broke out on Saturday in the Majlis Park forest area in the national capital on Saturday](http://newsorbit360.com/files/news/en/imgs/fire-breaks-out-in-majlis-park-forest-area-in-delhi.webp?height=520)
New Delhi [India], April 25 (ANI): A fire broke out on Saturday in the Majlis Park forest area in the national capital on Saturday. Fire tenders have been rushed to the spot, and efforts are underway to bring the blaze under control. Just hours earlier
1 days ago
![New Delhi [India], April 25 (ANI): A fire broke out in a tent warehouse in the Jyoti Nagar area of the national capital on Saturday](http://newsorbit360.com/files/news/en/imgs/fire-in-tent-warehouse-in-delhi-s-jyoti-nagar.webp?height=520)
New Delhi [India], April 25 (ANI): A fire broke out in a tent warehouse in the Jyoti Nagar area of the national capital on Saturday. Fire tenders are present at the scene, and efforts are underway to douse the flames. Deputy Chief Fire Officer of Delhi Fire Service MK Chattopadhyay said the fire
1 days ago
David Wilcock’s chilling 911 call reveal final moments, financial struggles: ‘I’m sorry to put you…'David Wilcock, 53, known for his UFO theories, died after battling depression and financial issues. A 911 call revealed his struggles before his death. Updated on: Apr 25
1 days ago
Apple’s new boss needs to restore its magic for the AI eraThe elevation of John Ternus hints at the future direction of the company Updated on: Apr 25, 2026 5:07 PM IST The Economist Share via Copy link JOHN TERNUS, named by Apple on April 20th as its new chief executive
1 days ago
Parineeti Chopra and Raghav Chadha, the most loved couple in town, continue to win hearts with their adorable bond and frequent public appearances together. Her politician husband has been hitting headlines ever since he announced his exit from the Aam Aadmi Party and his entry in the Bharatiya
1 days ago
The Reserve Bank of India (RBI) is working on a revised framework for Prepaid Payment Instruments (PPIs), the system behind digital wallets and prepaid cards. On Wednesday, the apex bank proposed a set of measures aimed at supporting their long-term growth
1 days ago
Woman shares how she found a PG in Bengaluru without stepping out: ‘Search, call, shortlist’A woman shared how she found a PG in Bengaluru from home and offered a simple three step guide for newcomers. Published on: Apr 25, 2026 3:19 PM IST By Mahipal Singh Chouhan Share via Copy link A
1 days ago
The Congress on Saturday (April 25, 2026) came out in solidarity with its leader, Pawan Khera and said the verdict of the Gauhati High Court rejecting his anticipatory bail petition would be challenged in the Supreme Court. Congress general secretary in-charge communications Jairam Ramesh expressed
1 days ago
Delhi Weather: Several parts of north India, including Delhi, are facing heatwave conditions, with temperatures crossing 40°C in most of the parts. The mercury may rise further by up to 3 degrees Celsius by April 29. Delhi Weather: Delhi witnessed intense heatwave conditions on Friday as the
1 days ago
Think that silver coin in your locker is a solid investment? You might want to double-check. The latest scam happened with Vaishno Devi Temple Trust, which had accumulated nearly 20 tonnes of silver coins offered by devotees over the years. Expecting a payout of over ₹500 crore
1 days ago
CBSE Three Language Policy: With only one foreign language allowed, most parents and students are choosing English, leaving almost no demand for languages like German or French. Under the Central Board of Secondary Education’s (CBSE) new three-language policy
1 days ago
![Jaipur (Rajasthan) [India], April 25 (ANI): Sunrisers Hyderabad's (SRH) swashbuckling opener Abhishek Sharma is just 26 runs away from surpassing Kane](http://newsorbit360.com/files/news/en/imgs/abhishek-sharma-just-26-runs-away-from-becoming-third-highest-run-scor.webp?width=120&height=70)
