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New Indian Express
3 days ago
- Climate
- New Indian Express
Forest fires surge in Northeast India due to climate variability, shows study
BHUBANESWAR: Forest fire has emerged as the latest threat to the lush, green expanse of Northeast India, often called the 'Seven Sister States'. A new scientific study has revealed an alarming rise in the intensity of forest fires in this ecologically fragile region due to climate variability. A team of climate and geospatial experts from India and Brazil have mapped over 3.6 lakh fire incidents across Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, and Tripura during 2001-2022 and analysed active fire points by using NASA's MODIS satellite, linking fire patterns to climatic factors like temperature, rainfall, solar radiation, and wind speed. Approximately 80% of annual forest fires were observed between March and April, with the years 2006, 2007, 2009, and 2010 marked by anomalously high fire incidences. Fire events were predominantly recorded in woodlands, shrublands, regrowth areas, evergreen forests, and cropland mosaics. The highest frequency of fire occurrences was reported in 2009, contributing 7.40% to the overall. This was closely followed by 2006, which contributed 7.34%. Among the Seven Sister States, Mizoram experienced the highest number of fire incidents, accounting for 24.2% of the total 3,60,383 incidents recorded during last two decades. It was followed by Assam (19.8%), Manipur (16.3%), Nagaland (11.8%), Arunachal Pradesh (9.1%) and Tripura (6.6%). The study has identified a strong correlation between fire occurrence and climatic factors, particularly low rainfall and high solar radiation.
NDTV
21-05-2025
- Science
- NDTV
NASA Satellite Shows World's Largest Iceberg Breaking Into Thousands Of Pieces. What Happens Next
The world's largest iceberg, A23a, is breaking apart into smaller pieces, posing a threat to humans and the millions of penguins in the nearby Antarctic sanctuary. NASA's Aqua satellite, equipped with MODIS (Moderate Resolution Imaging Spectroradiometer), has captured striking images of the massive iceberg A23a breaking apart. The photos show thousands of smaller ice chunks detaching from the iceberg's northern edge, creating a hazardous icy landscape in the surrounding area. The image highlights the iceberg's enormous size, comparable to South Georgia Island (approximately 1400 square miles), which is famously known for Ernest Shackleton's rescue mission after the Endurance shipwreck. "Thousands of iceberg pieces litter the ocean surface near the main berg, creating a scene reminiscent of a dark, starry night," wrote representatives with the space agency, NASA wrote in a statement. The "megaberg" A23a, currently the world's largest iceberg, has a surface area of approximately 1,200 square miles. It calved from Antarctica's Filchner-Ronne Ice Shelf in 1986 but remained trapped until 2023. After breaking free, it regained the title of largest iceberg in June 2023. A23a became stuck again in a vortex in early 2024 but broke free in December. It is now grounded off South Georgia Island, where it will likely remain until it melts or breaks apart in the "iceberg graveyard" of the Scotia Sea. As per NASA, the massive iceberg is breaking apart into smaller pieces through a process called "edge wasting." Although the new icebergs appear small compared to A23a, many are still around a kilometre across, posing a risk to ships. The largest piece to break off, dubbed A23c, measures approximately 50 square miles. Since getting stuck in March, A23a has shrunk by about 200 square miles. It's expected to take months or years for the iceberg to fully disintegrate. A23a's size lead is also narrowing, with another iceberg, D15A, closing in on its record. The Impact South Georgia Island is home to a diverse wildlife population, including seals, seabirds, and over 2 million penguins, but has a sparse human presence with only a few dozen researchers visiting annually. The massive iceberg A23a, currently grounded offshore, could potentially disrupt the ecosystem by forcing penguins to travel longer distances to find prey and altering the surrounding water temperature and salinity with its meltwater. Some of these fragments measure over half a mile wide and could therefore "pose a risk to ships," according to NASA. However, its relatively distant location from the coast may mitigate the impact. Some researchers suggest the melting iceberg could also have a positive effect by releasing nutrients into the ocean, benefiting the marine ecosystem. Scientists warn that similar events, such as massive iceberg break-offs, may become more frequent in the future because of climate change. This acceleration of ice shelf melting could have significant implications for global sea levels, ocean ecosystems and the planet's climate as a whole.
New York Post
20-05-2025
- Science
- New York Post
World's largest iceberg is breaking into thousands of pieces — putting people and wildlife at risk
The iceberg goeth? The world's largest iceberg, A23, is fragmenting into smaller pieces, potentially jeopardizing both humans and the millions of penguins in the neighboring Antarctic refuge. Alarming photos snapped by NASA's Aqua satellite have revealed that the periphery of the frozen mass is beginning to break apart, particularly along its northern edge, turning the surrounding area into an icy minefield. Advertisement 'Thousands of iceberg pieces litter the ocean surface near the main berg, creating a scene reminiscent of a dark starry night,' wrote representatives with the space agency, Live Science reported. 4 The MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA's Aqua satellite captured this image of the berg, named A23, on May 3, 2025. NASA This marks the culmination of an epic voyage for the so-called mega-berg, which boasts a surface area of 1,200 square miles — making it the largest iceberg in the world. Advertisement After being trapped on the ocean floor since 1986, the colossal ice cube broke away from its position several years back, and drifted into the Southern Ocean. A23's floe state was interrupted again in 2024, when it became stranded in a spinning vortex, before eventually breaking free and resuming its journey North. 4 A23 is the largest iceberg in the world. Getty Images Then in January, the mega-berg was spotted making a bee-line for South Georgia Island — a British territory known for its unique wildlife — but ground to a halt just 60 miles offshore, which scientists believe could be A23's final resting place. Advertisement While the sheet thankfully didn't run aground on the island, this frozen cluster bomb could still potentially threaten the millions of penguins and seals that reside there. 4 Researchers worry that A23 could obstruct penguin feeding routes. / Penguins could potentially need to navigate hundreds of miles around the moored ice mass to reach their feeding grounds while the mega-berg's meltwater could affect the temperature and salinity of the surrounding sea. In 2004, some of South Georgia's resident penguin chicks and seal pups died after an ice island named A38 broke off and obstructed their feeding routes. Advertisement Researchers hope A23's location far off the coast will hopefully mitigate its impact on the ecosystem. 4 This handout satellite image released by Copernicus Sentinel Data 2025, shows A23 getting closer to the South Georgia Island on February 24, 2025. COPERNICUS SENTINEL DATA 2025 /AFP via Getty Images Unfortunately, animals might not be the only ones who might be in danger during the ice floe's death throes. Some of these fragments measure over half a mile wide and could therefore 'pose a risk to ships,' according to NASA. The largest berg — which measures around 50 square miles — is currently drifting south out of view of the satellite photo. The situation perhaps inspires flashbacks of an incident in 2023 that occurred when a floe named A76 came close to grounding and left a veritable icy obstacle course in its wake. 'Those pieces basically cover the island (South Georgia) — we have to work our way through it,' said Captain Simon Wallace, who helms the South Georgia government vessel Pharos. Advertisement His crew has searchlights 'on all night' so they won't be blindsided by a berg. Despite literally falling to pieces, A23 won't be going away overnight as researchers estimate that it will take months or even years for the frozen juggernaut to disintegrate entirely. In the interim, A23 will likely lose its title of world's biggest iceberg. As of A23, the sheet is only around 12 square miles larger than the next-biggest iceberg, D15A.
Time of India
15-05-2025
- Science
- Time of India
Why the oceans are changing colour and what it means
For centuries, the poets and romantics have described the vast ocean as ethereal and striking blue. But now, satellites are revealing that Earth's oceans are subtly but significantly shifting in colour. A 2023 study led by B. B. Cael from the UK's National Oceanography Centre, published in Nature, found that over half of the world's ocean surface — 56% — has changed colour in the last 20 years. The likely driver? Human-induced climate change. Cael and fellow researchers from MIT and NASA used two decades of satellite data to monitor the ocean's colour spectrum, particularly through NASA's Aqua satellite and its MODIS instrument. This tool captures light in seven visible wavelengths, offering a deeper look at subtle shifts in the ocean's hue than earlier models ever could. The study's results were striking: tropical regions near the Equator are turning greener, while other zones, especially in low-productivity waters, are growing bluer. These shifts are tied closely to the health and distribution of phytoplankton — microscopic, plant-like organisms that not only fuel marine ecosystems but also influence the ocean's colour. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like The Highest Earning College Majors—2025 Edition Best Paying Degrees | Search Ads Learn More Undo Phytoplankton contain chlorophyll, which gives them a green tint and plays a key role in photosynthesis. When their populations grow or move, they scatter and absorb sunlight differently, changing how the ocean reflects light. This is why greener waters often suggest a higher concentration of life, while deeper blue indicates fewer organisms. The recent European State of the Climate report highlighted dramatic changes in chlorophyll levels: increases of 200–500% in the Norwegian Sea and North Atlantic in April 2023, and significant drops west of the Iberian Peninsula. In the Mediterranean, chlorophyll spiked 50–100% above average by June. These patterns suggest that warming seas are disrupting the balance of marine ecosystems, not just temporarily, but potentially long-term. What makes this even more concerning is that these colour changes are invisible to the naked eye. 'The colour itself is not something that you can even see that well,' Cael notes. Yet the shift is detectable through satellite data, and it's not confined to one region. 'We're seeing changes in all the major ocean basins.' This isn't the first time scientists have tried to predict such transformations. In 2019, MIT oceanographer Stephanie Dutkiewicz used models to project that ocean colours would eventually shift due to warming. But natural variability — like El Niño and La Niña — made it difficult to confirm. Cael's study, however, provides real-world evidence that confirms those predictions.
Time of India
10-05-2025
- Science
- Time of India
NASA satellites track plankton swarms from space to protect North Atlantic right whales
The North Atlantic Right Whale (NARW), one of the most critically endangered mammals on Earth, continues to be threatened with several dangers despite the prohibition of commercial whaling. Tired of too many ads? go ad free now Entanglement in fishing nets and collisions with ships are now the greatest dangers to their existence. To help protect these whales from these dangers, scientists have come up with creative ways of monitoring their habits and reducing these dangers. Another core part of this study is determining the whale's feeding habit, or how they depend on a specific species of plankton, Calanus finmarchicus, a reddish-colored copepod. Researchers are charting the density of these copepods from NASA satellite imagery and more precisely forecasting the whales' migratory routes. NASA tracks plankton populations from space to support right whale protection The NARW's food intake is the deciding factor on where they migrate across the ocean. The whales feed mainly on Calanus finmarchicus, a copepod that inhabits huge herds in the ocean. These herds are in certain places, and monitoring where they are is the key to being able to predict the migration of whales. The Gulf of Maine, one of the primary feeding grounds for NARWs, is a place where these copepods occur in large numbers. Researchers have also been looking to map the populations of these copepods so they can estimate where NARWs will be apt to feed, cutting down on ship collision hazards and net entanglements. Satellite technology has a key role to play in this research. Source: NASA To track the copepod blooms, scientists used the Moderate Resolution Imaging Spectroradiometer (MODIS), a sensor on NASA's Aqua satellite. Tired of too many ads? go ad free now MODIS monitors the manner in which sunlight reflecting off the sea surface varies as it travels through different materials in the water. In this case, it looks for astaxanthin, the red color in Calanus copepods. The occurrence of this pigment affects light scattering and absorption by the sea, which is a parameter that MODIS can observe. When the copepods form swarms in high density, the pigment changes the spectrum of reflected light, and scientists can remotely map their distribution. This is a non-destructive, large-scale technique for finding planktonic swarms without looking at them in situ in the ocean. Source: NASA How satellites use astaxanthin to track copepods Astaxanthin, the reddish pigment in copepods, is of pivotal importance when it comes to MODIS observing zooplankton in the ocean. As massive populations of copepods migrate towards the sea surface, the areal density of the pigment accumulates and thereby affects the scattering and absorption of photons by the ocean. All of these can be observed from orbit, and scientists now have means to quantify copepod population density. Researchers first tested the satellite-based copepod detection method in Norwegian waters but have now expanded the technique to the Gulf of Maine, an important feeding ground for North Atlantic Right Whales. Through the use of satellite measurements, field observations, and sophisticated modeling methods, scientists have improved their capacity to estimate the density of copepods in an area. By integrating data from several sources, scientists are able to paint more precise pictures and forecasts of Calanus swarms on the ocean surface. Through the combined method, it is possible to have better monitoring of whale feeding habits, which can be employed to inform conservation efforts and mitigate the associated risks. Challenges in satellite-based copepod detection Although promising, this satellite method has some drawbacks. The MODIS sensor is able to sense the red hue of the copepods but cannot actually sense the organisms themselves. This leaves open the potential for false positives—where the satellite can sense other reddish small animals that are not necessarily copepods. Moreover, satellite remote sensing can be disrupted by clouds and extremely rough seas to the extent that precise readings are not possible under some weather. In addition, if the copepod swarms are deeper in the water column, they cannot be reached from the surface. In its quest to bypass some of those limitations, is introducing the PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) satellite in 2024. The PACE mission has a great deal to bypass zooplankton and phytoplankton detecting ability, greatly lightening the job of monitoring for whales' target prey. Its satellite replacement will offer more accurate high-resolution observations and improved detection of plankton in different forms of the water, and handling cloud occlusions and the sort of churned ocean water which tends to plague cruise ships. By putting together more modern technology with current research methods, PACE is to provide much more accurate and reliable means of tracking and preserving the North Atlantic Right Whale population. Advancements in satellite tracking help protect right whales Observation of the North Atlantic Right Whale through their main source of food, the Calanus copepod, has become an essential component of whale conservation. Through a combination of satellite technology and new approaches, scientists are learning more about whale migration patterns, which may potentially translate to fewer cases of fatal encounters with fishing nets and boats. While the reliability of data and climatic conditions provide hurdles to cross, the future for ocean observation is bright with NASA's PACE satellite being launched, with still more accurate data to aid in the preservation of these terribly beleaguered animals. Also Read |
