Notable observations and news items from the Web, with no processing and little in the way of comment. Make of them what you will (updated whenever I have time).
The current extremely low sea ice will have a range of impacts. Changed ocean stratification and circulation will alter basal melting beneath ice shelves48. Greater coastal exposure will increase coastal erosion and reduce ice-shelf stability49. Changes in dense shelf water production will alter bottom water formation and deep ocean ventilation50. Sea ice changes will also have contrasting influences on Adélie and emperor penguin colonies51,52, and substantially alter human activities along the Antarctic coastline.
Anthropogenic greenhouse gas emissions have been attributed as the primary cause of Southern Ocean warming28,29, and here we suggest a potential link to a regime shift in Antarctic sea ice. While for many years, Antarctic sea ice increased despite increasing global temperatures6, it appears that we may now be seeing the inevitable decline, long projected by climate models53. The far-reaching implications of Antarctic sea ice loss highlight the urgent need to reduce greenhouse gas emissions.
Off the previous chart, again…. In 12 days another ~500,000 hectares have burned! Will the burning stop for winter? What does this portend for Australia’s upcoming El Nino summer?
https://www.theguardian.com/environment/2023/sep/11/us-record-billion-dollar-climate-disasters Note, as the frequency, extent, and ferocity of climate disasters continue to increase with accelerating global warming, newer disasters will overlap and add to destruction from previous disasters where there has not been enough time to complete repair and remediation leading to the accelerating accumulated climate damage — until society no longer has the resources to continue repairing and replacing what has already been repaired and replaced. At this point social collapse is inevitable…… We must stop and reverse the process of global warming that is causing this or face near-term extinction.
11 September 2023 – Coming out of winter — not a good look for the rest of the year in Australia!On 11 Sept., horrifically low extent of Antarctic sea ice has actually started melting on 8 Sept. Will there be any sea ice left at all in high summer?
In February 2023, Antarctic sea ice set a record minimum; there have now been three record-breaking low sea ice summers in seven years. Following the summer minimum, circumpolar Antarctic sea ice coverage remained exceptionally low during the autumn and winter advance, leading to the largest negative areal extent anomalies observed over the satellite era. Here, we show the confluence of Southern Ocean subsurface warming and record minima and suggest that ocean warming has played a role in pushing Antarctic sea ice into a new low-extent state. In addition, this new state exhibits different seasonal persistence characteristics, suggesting that the underlying processes controlling Antarctic sea ice coverage may have altered.
a Antarctic monthly sea ice extent (SIE) anomaly time series from the National Snow and Ice Data Center over the satellite period, November 1978 to June 2023, in millions of square kilometres. Sea ice extent anomalies are calculated relative to the 1979–2022 climatology. Two change points are detected, separating the time series into three periods: November 1978 to August 2007 (grey), September 2007 to August 2016 (blue), and September 2016 to June 2023 (orange). The means of each period are shown by the horizontal lines and are statistically distinguishable. b Antarctic monthly SIE anomaly time series expressed as a percentage of the monthly climatology over 1979–2022. Periods are coloured as in (a). Record minima months occurring since 2016 are noted in (a, b). c Southern Ocean 50–65°S temperature anomaly time series from Argo over January 2004 to May 2023, in degrees Celsius. Ocean temperature anomalies are calculated relative to the 2004-2022 climatology. Dashed vertical lines show the sea ice extent change points. Stippling indicates values outside ± 1 standard deviation, where the standard deviation is calculated independently at each depth level to account for the change in magnitude of the variability with depth. Warm anomalies shown in orange and red are evident below 100 m from 2015, and at the surface from late 2016.Antarctic five-day sea ice extent anomalies in millions of square kilometres for each year from the National Snow and Ice Data Center. Sea ice extent anomalies are calculated relative to the 1979–2022 climatology. Anomalies are coloured by period as in Fig. 1: November 1978 to August 2007 (grey), September 2007 to August 2016 (blue), and September 2016 to June 2023 (orange). January to June 2023 is shown in bold orange, with the largest negative areal extent anomaly of the satellite era observed during June 2023.
Implications
The current extremely low sea ice will have a range of impacts. Changed ocean stratification and circulation will alter basal melting beneath ice shelves48. Greater coastal exposure will increase coastal erosion and reduce ice-shelf stability49. Changes in dense shelf water production will alter bottom water formation and deep ocean ventilation50. Sea ice changes will also have contrasting influences on Adélie and emperor penguin colonies51,52, and substantially alter human activities along the Antarctic coastline.
Anthropogenic greenhouse gas emissions have been attributed as the primary cause of Southern Ocean warming, and here we suggest a potential link to a regime shift in Antarctic sea ice. While for many years, Antarctic sea ice increased despite increasing global temperatures, it appears that we may now be seeing the inevitable decline, long projected by climate models. The far-reaching implications of Antarctic sea ice loss highlight the urgent need to reduce greenhouse gas emissions.
Not yet getting back to anything as cool as last year’s near record highs after more than 3 months! – https://climatereanalyzer.org/clim/t2_daily/?dm_id=world3+ months and the anomaly is still trending ever more extreme as the sub-solar point moves towards the Southern Hemisphere!Global Average Sea Surface Temperature still above previous years ALL TIME RECORD HIGH TEMPERATURE with trend line still widening the gap. 90% of excess solar heat is first absorbed into the oceans to heat the globe as a whole. – https://climatereanalyzer.org/clim/sst_daily/Southern Hemisphere anomaly also in record extreme territory and rising rapidly. Antarctic rising and ~1 day from record daily high.Sept. 13 and Antarctic sea ice already beginning to melt after 4+ months of record low freezing rate, to create a global average record low amounts of sea ice. At the southern summer low to come will there be ANY sea ice left around Antarctica? What does this mean for ice shelves and glacier fronts exposed to warm pounding waves and tides? – https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/Sept. 19 and the ice is rapidly melting into ever more extreme low sea ice for the date.https://seaice.visuals.earth/ Sept 19 and rapid Antarctic melting keeps global coverage more than 4 σ below any previous low for the date. Not good news for southern summer! Record high temperatures & reduced temperatures between polar and ‘temperate’ zones lead to crazy, weak and chaotic jet streams; in turn allowing stalled extreme heat domes, droughts and wildfires; lethally moist air masses, biblical flooding, and catastrophic storms. OUR GOVERNMENTS ARE STILL PROMOTING AND SUBSIDIZING FOSSIL FUEL BURNING!
It’s truly astonishing how hot the North Atlantic was this summer. 2.3F above normal (+1.3C) and about 1F or .5C above records. It may not sound like much but it’s tremendous – This is for a huge area from the equator to the southern tip of Greenland and from Florida to the UK. https://t.co/M6Wapdbo5jpic.twitter.com/D2mj0iKBRy
[Note that 2020- Siberian wildfires plus this years’ wildfires in the Canadian Arctic Zone probably produced massive increases in permafrost GHG emissions beyond what was happening during the years included in this survey.]
Map of northern permafrost extent (data from Obu et al. 2021) overlain with the spatial extent of the permafrost domain included (BAWLD-RECCAP2 regions). The spatial extent of the permafrost region de ned in this study as an overlap of permafrost extent and the Boreal Arctic Wetlands and Lakes Dataset (BAWLD, Olefeldt et al. 2021a,bScheme of annual atmospheric GHGs exchange (CO2, CH4, and N2O) for the ve terrestrial land cover classes (Boreal Forests, Non-permafrost Wetlands, Dry Tundra, Tundra Wetlands and Permafrost Bogs); inland water classes (Rivers and Lakes). Annual lateral fluxes from coastal erosion and riverine fluxes are also reported in Tg C yr-1 and Tg N yr-1. Symbols for fluxes indicate high (x>Q3), medium (Q1<x<Q3), and low (<Q1) fluxes, in comparison the quartile (Q). Note that the magnitudes across three di erent GHG fluxes within each land cover class cannot be compared with each other.
Some call me a 'climate scientist'. I'm not. What I am is an 'Earth systems generalist'.
Born in 1939, I grew up with passionate interests in both science and engineering. I learned to read from my father's university textbooks in geology and paleontology, and dreamed of building nuclear powered starships. Living on a yacht in Southern California I grew up surrounded by (and often immersed in) marine and estuarine ecosystems while my father worked in the aerospace engineering industry.
After studying university physics for three years, dyslexia with numbers convinced me to change my focus to biology. I completed university as an evolutionary biologist (PhD Harvard, 1973). My principal research project involved understanding how species' genetic systems regulated the evolution and speciation of North America's largest and most widespread lizard genus. Then for several years as an academic biologist I taught a range of university subjects as diverse as systematics, biogeography, cytogenetics, comparative anatomy and marine biology.
In Australia, from 1980, I was involved in various activities around the emerging and rapidly evolving microcomputing technologies culminating in 2 years involvement in the computerization of the emerging Bank of Melbourne.
In 1990 I joined a startup engineering company that had just won the contract to build a new generation of 10 frigates for Australia and New Zealand. In 2007 I retired from the head office of Tenix Defence, then Australia's largest defence engineering contractor, after a 17½ year career as a documentation and knowledge management systems analyst and designer. At Tenix I reported to the R&D manager under the GM Engineering, and worked closely with support and systems engineers on the ANZAC Ship Project to solve documentation and engineering change management issues that risked the project 100s of millions of dollars in cost and years of schedule overruns. All 10 ships had been delivered on time, on budget to happy customers against the fixed-price and fixed schedule contract.
Before, during, and after these two main gigs I also did a lot of other things that contribute to my general understanding of complex dynamical systems involving multiple components with non-linear and sometimes chaotically interacting components; e.g., 'Earth systems'.
Earth's Climate System is the global heat engine driven by the transport and conversions of energy between the incoming solar radiation striking the planet, and the infrared radiation of heat away from the planet to the cold dark universe.
As Climate Sentinel News Editor, my task is to identify and understand quirks and problems in the operation of this complex heat engine that threaten human existence, and explain to our readers how they can help to solve some of the critical issues that are threatening their own existence.
