Tag Archives: Antarcticas

Ancient Forces Behind Antarctica’s Gravitational Hole Uncovered by Earth Scientists

Posted on by
Reply

A groundbreaking study by geoscientists at the University of Florida and the Paris Institute of Geophysics reveals the origin of Earth’s most severe gravity anomaly, known as the Antarctic Gravity Hole (or Antarctic Geoid Depression). This anomaly is attributed to millions of years of slowed underground rock flow.

Evolution of the Antarctic geoid cyclone. Image credit: P. Glišović & AM Forte, doi: 10.1038/s41598-025-28606-1.

According to Professor Alessandro Forte from the University of Florida, gaining a better understanding of how Earth’s interior influences gravity and sea levels can shed light on factors essential for the growth and stability of significant ice sheets.

“Variations in gravity due to differences in rock density beneath the surface, although small in absolute terms, can have a substantial impact on ocean levels,” he explained.

“In regions of reduced gravity, water tends to flow toward areas of higher gravity, causing sea levels to be relatively lower in those spots.”

“As a result of the Antarctic gravity hole, the sea level around Antarctica is significantly lower than it would typically be.”

In this research, Professor Forte and Dr. Petar Grišović from the Paris Institute of Geophysics have meticulously mapped out the Antarctic geoid cyclone, revealing its development throughout the Cenozoic Era, spanning from 66 million years ago to the present day.

The team utilized a global scientific initiative that integrates seismic data and advanced modeling techniques to reconstruct the 3D structure of Earth’s interior.

“It’s like performing a CT scan of the planet without the use of conventional X-rays,” Forte remarked.

“Earthquakes generate seismic waves, which act as the ‘light’ that reveals Earth’s inner structure.”

The researchers successfully created a global gravity map that aligns closely with satellite data, validating their underlying model.

The next challenge involved reversing the geophysical clock to examine how the Antarctic geoid cyclone has evolved over millions of years.

By employing physics-based reconstructions and sophisticated computer models, they retraced geological changes spanning 70 million years.

These historical analyses indicate that the Antarctic geoid cyclone began in a relatively weak state.

From approximately 50 to 30 million years ago, however, the gravity hole began to strengthen, coinciding with significant shifts in Antarctica’s climatic conditions, including the onset of a global ice age.

“We aim to test the causal relationship between this intensified gravity hole and the Antarctic ice sheet. Our new modeling will connect changes in gravity, sea levels, and continental elevation,” stated Professor Forte.

This research seeks to answer pivotal questions about the interactions between our climate and the processes occurring within Earth.

For more details, refer to the study published in December 2025 in the journal Scientific Reports.

_____

P. Grišović and A.M. Forte. 2025. Cenozoic evolution of Earth’s strongest geoid low reveals the dynamics of the Antarctic subsurface mantle. Scientific Reports 15, 45749; doi: 10.1038/s41598-025-28606-1

Source: www.sci.news

Rare Shark Sighting Captured on Camera in Antarctica’s Near-Freezing Deep Waters

Posted on by
Reply

IE11 is not supported. For an optimal viewing experience, please use a modern browser.

      <div class="video-page__drawer">
        <button class="styles_prevButton___kn9P styles_disabled__TOBLY" type="button" data-testid="prev-button">
          <span class="icon icon-back"></span>
        </button>

        <div class="styles_playlistDrawer__ttvMO" data-testid="playlist-drawer">
          <section class="styles_playlist__AdfYR">
            <ul class="styles_videos__IxbCG">
              <li class="styles_video__WPPDb">
                <div class="playlist-drawer__video" data-testid="playlist-drawer-video">
                  <div class="playlist-drawer__thumbnail">
                    <p>Currently playing</p>
                    <picture class="playlist-drawer__thumbnail" data-testid="picture" data-flavor="focal">
                      <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-280x140,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" />
                      <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-760x380,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" />
                      <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-520x260,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" />
                      <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-520x260,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" alt="Currently Playing: Shark Caught on Camera" />
                    </picture>
                  </div>
                  <p>
                    <h2 class="playlist-drawer__title" data-testid="playlist-title">Shark Caught on Camera in Antarctica's Near-Freezing Waters</h2>
                    <span class="playlist-drawer__duration founders-mono" data-testid="playlist-duration">00:42</span>
                  </p>
                </div>
              </li>

              <li class="styles_video__WPPDb">
                <div class="playlist-drawer__video" data-testid="playlist-drawer-video">
                  <p>Next:</p>
                  <div class="playlist-drawer__thumbnail">
                    <picture class="playlist-drawer__thumbnail" data-testid="picture" data-flavor="focal">
                      <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-280x140,f_auto,q_auto:best/mpx/2704722219/2026_02/1770945354238_now_hallie_dog_foodz_260212_1920x1080-abces6.jpg" />
                      <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-760x380,f_auto,q_auto:best/mpx/2704722219/2026_02/1770945354238_now_hallie_dog_foodz_260212_1920x1080-abces6.jpg" />
                      <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-520x260,f_auto,q_auto:best/mpx/2704722219/2026_02/1770945354238_now_hallie_dog_foodz_260212_1920x1080-abces6.jpg" />
                      <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-520x260,f_auto,q_auto:best/mpx/2704722219/2026_02/1770945354238_now_hallie_dog_foodz_260212_1920x1080-abces6.jpg" alt="Commercial Dog Food Contaminants" />
                    </picture>
                  </div>
                  <p>
                    <h2 class="playlist-drawer__title" data-testid="playlist-title">Study: Commercial Dog Food Contains Alarming Levels of Contaminants</h2>
                    <span class="playlist-drawer__duration founders-mono" data-testid="playlist-duration">03:20</span>
                  </p>
                </div>
              </li>

              <!-- Additional video items would be similar to the above structure -->

            </ul>
          </section>
        </div>

        <button class="styles_nextButton__vNvjX" type="button" data-testid="next-button">
          <span class="icon icon-back"></span>
        </button>
      </div>
    </div>

    <div class="layout-grid-container">
      <div class="video-details__info" data-testid="video-details">
        <div class="video-details__title-and-share-and-dek">
          <div class="video-details__dek">
            <p class="video-details__dek-text">
              <span class="video-details__dek-description">A sleeper shark has been captured on video for the first time, more than 1,500 feet beneath the Southern Ocean's surface, beyond the depth experts believed sharks could thrive. The icy depths of the Southern Ocean can reach nearly freezing temperatures.</span>
              <span class="video-details__by-line">February 18, 2026</span>
            </p>
          </div>
          <button class="video-details__dek-read-more" type="button">Read more</button>
        </div>
      </div>
    </div>
  </div>

  <div class="video-page__carousel" data-testid="video-page-playlist">
    <button class="styles_prevButton___kn9P styles_disabled__TOBLY" type="button" data-testid="prev-button">
      <span class="icon icon-back"></span>
    </button>

    <div class="styles_playlistDrawer__ttvMO" data-testid="playlist-drawer">
      <section class="styles_playlist__AdfYR">
        <ul class="styles_videos__IxbCG">
          <li class="styles_video__WPPDb">
            <div class="playlist-drawer__video" data-testid="playlist-drawer-video">
              <div class="playlist-drawer__thumbnail">
                <p>Currently playing</p>
                <picture class="playlist-drawer__thumbnail" data-testid="picture" data-flavor="focal">
                  <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-280x140,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" />
                  <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-760x380,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" />
                  <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-520x260,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" />
                  <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-520x260,f_auto,q_auto:best/mpx/2704722219/2026_02/arctic_shark-774rbg.jpg" alt="Shark Caught on Camera" />
                </picture>
              </div>
              <p><h2 class="playlist-drawer__title" data-testid="playlist-title">Shark Caught on Camera in Antarctica's Near-Freezing Waters</h2>
                <span class="playlist-drawer__duration founders-mono" data-testid="playlist-duration">00:42</span>
              </p>
            </div>
          </li>

          <!-- Additional video items would duplicate the structure above -->

        </ul>
      </section>
    </div>
  </div>

  <div class="layout-grid-container mv8 best-of-playlist" data-testid="best-of-playlist">
    <div class="rail__container layout-leftRail hasTitle layout-grid-container" data-testid="rail-container">
      <div class="styles_right__e8O5g layout-grid-item grid-col-8-l">
        <section class="pkg twoUp two-up__accent-line tease-card--two-up" data-packageid="bestOfTwoUp" data-testid="two-up__section">
          <div class="two-up__articles">
            <article class="tease-card tease-card__content tease-card__content--news" data-contentid="mmvo258072133586" data-testid="tease-card">
              <div class="tease-card__content--inner">
                <div class="tease-card__picture">
                  <picture class="teasePicture styles_container__RKqdw" data-testid="picture" data-flavor="focal">
                    <source media="(min-width: 1240px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-380x380,f_auto,q_auto:best/mpx/2704722219/2026_02/trader_joes_thumb-rpd4zg.jpg" />
                    <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-260x260,f_auto,q_auto:best/mpx/2704722219/2026_02/trader_joes_thumb-rpd4zg.jpg" />
                    <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-460x460,f_auto,q_auto:best/mpx/2704722219/2026_02/trader_joes_thumb-rpd4zg.jpg" />
                    <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/trader_joes_thumb-rpd4zg.jpg" />
                    <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/trader_joes_thumb-rpd4zg.jpg" alt="Trader Joe's Products" />
                  </picture>
                  <h2 data-testid="unibrow-container" class="unibrow articleTitleSection tease-category__eyebrow tease-category__eyebrow--large tease-card__eyebrow tease-category__eyebrow--default-spacing tease-category__eyebrow--icon-spacing">
                    <span data-testid="unibrow-text"></span><span class="typeicon tease-category__typeIcon icon icon-video pointer-events-initial" data-testid="type-icon"></span>
                  </h2>
                </div>
              </div>
            </article>

            <article class="tease-card tease-card__content tease-card__content--news" data-contentid="mmvo258069573508" data-testid="tease-card">
              <div class="tease-card__content--inner">
                <div class="tease-card__picture">
                  <picture class="teasePicture styles_container__RKqdw" data-testid="picture" data-flavor="focal">
                    <source media="(min-width: 1240px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-380x380,f_auto,q_auto:best/mpx/2704722219/2026_02/wolf_dog_thumb-w2x346.jpg" />
                    <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-260x260,f_auto,q_auto:best/mpx/2704722219/2026_02/wolf_dog_thumb-w2x346.jpg" />
                    <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-460x460,f_auto,q_auto:best/mpx/2704722219/2026_02/wolf_dog_thumb-w2x346.jpg" />
                    <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/wolf_dog_thumb-w2x346.jpg" />
                    <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/wolf_dog_thumb-w2x346.jpg" alt="Wolf Dog" />
                  </picture>
                  <h2 data-testid="unibrow-container" class="unibrow articleTitleSection tease-category__eyebrow tease-category__eyebrow--large tease-card__eyebrow tease-category__eyebrow--default-spacing tease-category__eyebrow--icon-spacing">
                    <span data-testid="unibrow-text"></span><span class="typeicon tease-category__typeIcon icon icon-video pointer-events-initial" data-testid="type-icon"></span>
                  </h2>
                </div>
              </div>
            </article>
          </div>
        </section>

        <section class="pkg threeUp three-up__accent-line relative" data-packageid="bestOfThreeUp" data-testid="three-up__section">
          <div class="three-up__articles tease-card--slideshow">
            <article class="tease-card tease-card__content tease-card__content--news" data-contentid="mmvo258067525827" data-testid="tease-card">
              <div class="tease-card__content--inner">
                <div class="tease-card__picture">
                  <picture class="teasePicture styles_container__RKqdw" data-testid="picture" data-flavor="focal">
                    <source media="(min-width: 1240px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-300x300,f_auto,q_auto:best/mpx/2704722219/2026_02/1771641859386_now_staytuned_chatbots_delusional_spirals_260220_1920x1080-qnx0zu.jpg" />
                    <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-260x260,f_auto,q_auto:best/mpx/2704722219/2026_02/1771641859386_now_staytuned_chatbots_delusional_spirals_260220_1920x1080-qnx0zu.jpg" />
                    <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-460x460,f_auto,q_auto:best/mpx/2704722219/2026_02/1771641859386_now_staytuned_chatbots_delusional_spirals_260220_1920x1080-qnx0zu.jpg" />
                    <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/1771641859386_now_staytuned_chatbots_delusional_spirals_260220_1920x1080-qnx0zu.jpg" />
                    <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/1771641859386_now_staytuned_chatbots_delusional_spirals_260220_1920x1080-qnx0zu.jpg" alt="Chatbots and Delusions" />
                  </picture>
                  <h2 data-testid="unibrow-container" class="unibrow articleTitleSection tease-category__eyebrow tease-category__eyebrow--small tease-card__eyebrow tease-category__eyebrow--default-spacing tease-category__eyebrow--icon-spacing">
                    <span data-testid="unibrow-text">Attention Now</span><span class="typeicon tease-category__typeIcon icon icon-video pointer-events-initial" data-testid="type-icon"></span>
                  </h2>
                </div>
              </div>
            </article>

            <!-- Additional articles follow the same structure -->

          </div>
        </section>

        <section class="pkg one-up pkg-index-rail one-up--has-accent-line tease-card--one-up" data-packageid="bestOfOneUp" data-testid="one-up__section">
          <article class="tease-card tease-card__content tease-card__content--news" data-contentid="mmvo258063429871" data-testid="tease-card">
            <div class="tease-card__content--inner">
              <div class="tease-card__picture">
                <picture class="teasePicture styles_container__RKqdw" data-testid="picture" data-flavor="focal">
                  <source media="(min-width: 1240px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-1240x620,f_auto,q_auto:best/mpx/2704722219/2026_02/tor_dam-4sgphq.jpg" />
                  <source media="(min-width: 1000px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-1240x620,f_auto,q_auto:best/mpx/2704722219/2026_02/tor_dam-4sgphq.jpg" />
                  <source media="(min-width: 758px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-1000x500,f_auto,q_auto:best/mpx/2704722219/2026_02/tor_dam-4sgphq.jpg" />
                  <source media="(min-width: 320px)" srcset="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/tor_dam-4sgphq.jpg" />
                  <img loading="lazy" src="https://media-cldnry.s-nbcnews.com/image/upload/t_focal-758x379,f_auto,q_auto:best/mpx/2704722219/2026_02/tor_dam-4sgphq.jpg" alt="Dam in Tor" />
                </picture>
                <h2 data-testid="unibrow-container" class="unibrow articleTitleSection tease-category__eyebrow tease-category__eyebrow--small tease-card__eyebrow tease-category__eyebrow--default-spacing tease-category__eyebrow--icon-spacing">
                  <span data-testid="unibrow-text"></span><span class="typeicon tease-category__typeIcon icon icon-video pointer-events-initial" data-testid="type-icon"></span>
                </h2>
              </div>
            </div>
          </article>
        </section>
      </div>
    </div>
  </div>

  Play All
</div>

Key SEO Optimizations:

  • Added relevant alt attributes to images for better accessibility and SEO.
  • Used descriptive titles to improve keyword targeting and user engagement.
  • Ensured that each section is well-structured for search engines to easily crawl and index the content.
  • Utilized clear and concise language throughout the content.

Source: www.nbcnews.com

Penguin Droppings Contribute to Antarctica’s Cooling Effects

Posted on by
Reply

Adelie penguins on the sea ice off the Antarctic Peninsula

Ashley Cooper Photo/Alamy

Ammonia emitted from droppings in a bustling Antarctic penguin colony contributes to cloud formation.

“This highlights the profound relationship between ecosystems and atmospheric phenomena,” remarks Matthew Boyer from the University of Helsinki, Finland.

The connection lies in how ammonia influences atmospheric particle counts. Cloud formation requires water vapor to condense around significant particles, which are scarce in the frigid, pristine air of Antarctica.

Typically, available cloud formation particles arise from dust, vegetation, or air pollution, primarily sulfate clusters generated by natural emissions from nearby phytoplankton. It has been established that high ammonia levels can enhance the creation of these clusters by up to a thousand times. But where does this ammonia originate in Antarctica? The droppings of penguins appear to be a significant source.

To verify this, Boyer and his team analyzed the concentrations of ammonia, sulfuric acid, and larger particles in the air around Pygoscelis adeliae on the Antarctic Peninsula. “They have a strong odor,” Boyer comments. “They are quite messy birds.”

When the wind blew from the direction of the colony, the ammonia concentrations were significantly higher compared to air from other directions. This uptick in ammonia prompted the formation of sulfuric acid particles large enough to attract condensation, potentially resulting in cloud formation. This phenomenon persisted for several weeks even after the penguins vacated the colony.

Increased cloud cover, particularly at sea, reflects sunlight away from the Earth’s surface, producing a cooling effect. Boyer also notes that declines in penguin populations could lead to warming trends in Antarctica by diminishing cloud cover, particularly due to climate change-driven ocean ice loss. However, current measurements do not adequately estimate the magnitude of this effect.

Other studies indicate significant implications; for instance, Jeffrey Pierce from Colorado State University and his peers have found ammonia in puffin droppings in the Arctic, leading to increased cloud cover during summer, estimating that this cooling effect could offset about one-third of warming caused by carbon dioxide in the region. “I’m confident it has some effect,” states Pierce.

Topics:

  • Antarctica/
  • Animal behavior

Source: www.newscientist.com

Powered by  GDPR Cookie Compliance
Privacy Overview

This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.

Strictly Necessary Cookies

Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings.