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Icebergs melting from underneath. Huge amount of ice melting too so quite alarming

Pic: Bronwyn Stevens, currently in the Antarctic

Pic by Bronwyn Stevens – currently in the Antarctic: “Icebergs melting from underneath. Huge amount of ice melting too so quite alarming”.

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10 Comments

10 Comments

  1. Lyndall

    March 30, 2019 at 10:55 am

    Just in case you missed it, the World Meteorological Organization released its statement on the State of the Climate 2018 on 28 Mar 2019.

    The full statement and press release can be found here:
    https://public.wmo.int/en/media/press-release/state-of-climate-2018-shows-accelerating-climate-change-impacts

    Overall, the results show accelerating climate change impacts.

    The WMO takes an holistic approach to its evaluation of climate change impacts including socio-economic impacts along with the measured changes occurring in the environment. Extracts from the press release below:

    “Hazards: In 2018, most of the natural hazards which affected nearly 62 million people were associated with extreme weather and climate events.

    Floods – Floods continued to affect the largest number of people, more than 35 million, according to an analysis of 281 events recorded by the Centre for Research on the Epidemiology of Disasters (CRED) and the UN International Strategy for Disaster Risk Reduction.

    Hurricanes & typhoons – Hurricane Florence and Michael were two of fourteen “billion dollar disasters” in 2018 in the United States of America (USA). They triggered around US$49 billion in damages and over 100 deaths. Super typhoon Mangkhut affected more than 2.4 million people and killed at least 134 people, mainly in the Philippines.

    Heatwaves & wildfires – More than 1600 death were associated with intense heat waves and wildfires in Europe, Japan and USA, where they were associated with record economic damages of nearly US$24 billion in USA.

    Food security: Exposure of the agriculture sector to climate extremes …

    Displacement: Out of the 17.7 million Internally Displaced Persons (IDPs) tracked by the International Organization for Migration, over 2 million people were displaced due to disasters linked to weather and climate events as of September 2018. Drought, floods and storms (including hurricanes and cyclones) are the events that have led to the most disaster-induced displacement in 2018. In all cases, the displaced populations have protection needs and vulnerabilities.

    Heat, Air Quality and Health: There are many interconnections between climate and air quality, which are being exacerbated by climate change.

    Environmental Impacts include coral bleaching and reduced levels of oxygen in the oceans. Others include loss of “Blue Carbon” associated with coastal ecosystems such as mangroves, seagrasses and salt marshes; and ecosystems across a range of landscapes.

    Climate change has emerged as a significant threat to peatland ecosystems, because it exacerbates the effects of drainage and increases fire risk, according to UN-Environment. Peatlands are important to human societies around the world. They contribute significantly to climate change mitigation and adaptation through carbon sequestration and storage, biodiversity conservation, water regime and quality regulation, and the provision of other ecosystem services that support livelihoods.

    Climate indicators

    Ocean heat: 2018 saw new records for ocean heat content in the upper 700 metres (data record started in from 1955) and upper 2000m (data record started in 2005), topping the previous record set in 2017. More than 90% of the energy trapped by greenhouse gases goes into the oceans and ocean heat content provides a direct measure of this energy accumulation in the upper layers of the ocean.

    Sea level: Sea level continues to rise at an accelerated rate. Global Mean Sea Level (GMSL) for 2018 was around 3.7 millimetres higher than in 2017 and the highest on record. Over the period January 1993 to December 2018, the average rate of rise is 3.15 ± 0.3 mm yr-1 while the estimated acceleration is 0.1 mm yr-2. Increasing ice mass loss from the ice sheets is the main cause of the GMSL acceleration as revealed by satellite altimetry, according to the World Climate Research Programme global sea level budget group, 2018.

    Ocean acidification: In the past decade, the oceans absorbed around 30% of anthropogenic CO2 emissions. Absorbed CO2 reacts with seawater and changes the pH of the ocean. This process is known as ocean acidification, which can affect the ability of marine organisms such as molluscs and reef-building corals, to build and maintain shells and skeletal material. Observations in the open-ocean over the last 30 years have shown a clear trend of decreasing pH.

    Sea ice: Arctic sea-ice extent was well below average throughout 2018 and was at record-low levels for the first two months of the year. The annual maximum occurred in mid-March and was the third lowest March extent in the 1979-2018 satellite record. The Greenland ice sheet has been losing ice mass nearly every year over the past two decades. … having lost approximately 3,600 gigatons of ice mass since 2002. A recent study also examined ice cores taken from Greenland, which captured melting events back to the mid 1500s. The study determined that the recent level of melt events across the Greenland ice sheet have not occurred in at least the past 500 years.

    Glacier Retreat: The World Glacier Monitoring Service monitors glacier mass balance using a set of global reference glaciers with more than 30 years of observations between 1950 and 2018. They cover 19 mountain regions. Preliminary results for 2018, based on a subset of glaciers, indicate that the hydrological year 2017/18 was the 31st consecutive year of negative mass balance.”

  2. Lyndall

    March 26, 2019 at 8:53 am

    Here’s some additional information about discharge increasing from our largest east Antarctic glacier and potential for sea level rise:

    ABC News online 25/03/2019 – https://twitter.com/YouStormorg/status/1110169851065040897

    “Scientists using seismic testing at the largest glacier in east Antarctica find massive subglacial lakes beneath its surface — which they say radically alters estimates on predicted sea level rise.

    A team of international researchers from the Australian Antarctic Program have this week returned from a 160-day expedition at the Totten Glacier, located near Casey Station — about 3,431 kilometres (2,132 miles) from Hobart. …

    Dr Galton-Fenzi said “a substantial amount of water” was contained in the subglacial lakes, which could impact the rate at which ice flows into the ocean. …

    While the Intergovernmental Panel on Climate Change (IPCC) estimates sea levels will rise by a metre by 2100, Dr Galton-Fenzi said those estimates did not factor in the increased discharge of Antarctic ice due to climate change. …

    “The Totten Glacier drains an area of east Antarctica that contains about seven metres of sea level rise equivalent of ice,” he said. … “We actually know for a fact that the Totten Glacier is one of the regions that’s actually changing.

    “We know there’s warm water present under the glacier, so we expect this is one of the regions in east Antarctica that’s going to change first.”

  3. MjF

    March 1, 2019 at 12:24 pm

    “Icebergs melting from underneath or huge amounts of ice melting too”. Which is the point of the article ?

    • max

      March 1, 2019 at 2:27 pm

      MJF… I would have thought the point is obvious. Icebergs float and warming water is melting them from underneath. At the same time the air temperature is also rising and land ice and icebergs are melting from the top down.

      • MjF

        March 1, 2019 at 6:18 pm

        All icebergs melt from underneath as they always eventually encounter warmer waters than where they originate. This is not news.

        The image taker doesn’t mention melting from the top down either. A little poetic licence from max.

        A non-story worthy of The Guardian.

        • max

          March 1, 2019 at 8:16 pm

          MJF … The antarctic oceanic is warming, therefore the icebergs are melting from underneath, they no longer have to float into warmer water.
          “The image taker doesn’t mention melting from the top down either. A little poetic licence from max.”
          “Huge amount of ice melting too so quite alarming”. Self explanatory” It is impossible for ice to melt from the inside out, air warmed ice melts from the top where it comes in contact with the warming air. No poetic licence Martin, just plain common sense. Common sense is something you continually prove to have in short supply.

          • Russell

            March 3, 2019 at 10:21 am

            They actually can melt from the inside out when a hole forms and the melting outside layer pours down through the holes to melt the core.

        • PLB

          March 1, 2019 at 8:22 pm

          This is news.
          Max may very well be poetic, but regardless, this is still news.
          The Guardian is not the only news outlet with this news article. Sloppy, lack of research again ….. MJF
          So, as a helpful personality, who would like to see your knowledge base expand/expanded, just so you can be the wise one, when standing around the BBQ knocking back a few cold ones, whilst telling Greenie jokes as the global climate continues to deteriorate, this Link ‘may’ help ……. https://www.scientificamerican.com/article/why-are-glaciers-melting-from-the-bottom-its-complicated/

    • Keith Antonysen

      March 2, 2019 at 5:35 pm

      Maybe there is a problem with terminology, rather than ” ice bergs” , “ice shelf” might be meant. Ice shelfs are bedded to grounding lines where they meet the ocean. Relatively warm water undermines those grounding lines and allows for movement seaward. When fissures are created at the surface of the glacier it speeds up the process. There is a huge area twice the area of New York of ice about to be lost from the Brunt ice shelf. The area is around 660 square miles which is about to be lost, though it is dwarfed by the Larson C ice shelf where 2,200 square miles of ice was lost in 2017.

  4. max

    February 28, 2019 at 3:50 pm

    So what, it is global warming, I love being warm. There will still be enough ice left in the Arctic and Antarctic for my whiskey. It will see me out. As long as there is enough fossil fuels left to keep keep me in the manner I am accustomed to, why should I worry? Morrison has got it all worked out, he knows he can promise the world, put Labour in dept with his grandiose ideas if he doesn’t get elected and break his promise if he does.

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