Sunday 27 November 2022

CSIRO-BOM State of the Climate 2022 report and what it says about the World, Australia & the NSW Coastal Zone


“There are no surprises here and the story hasn’t changed. It’s happening, it’s serious and we need to do something about it.” [CSIRO Ocean & Atmosphere Business Unit, Research Director at Climate Science Centre, Dr. Jaclyn Brown, The Guardian, 23 November 2022]


Yes, the story hasn't changed. However, the details are becoming clearer as to how, when and to what degree there will be disruption to Australian society, the national economy and food security  along with increasing risks to the health, safety and well being of the entire population  before national collapse occurs.


Once every two years the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in partnership with the Australian Bureau of Meteorology (BOM) produce a State of the Climate report.


The current 2022 report is the seventh report in the series. Previous reports can be found here.


The key points in State of the Climate 2022 are as follows:


Australia


  • Australia’s climate has warmed by an average of 1.47 ± 0.24 °C since national records began in 1910.

  • Sea surface temperatures have increased by an average of 1.05 °C since 1900. This has led to an increase in the frequency of extreme heat events over land and sea.

  • There has been a decline of around 15 per cent in April to October rainfall in the southwest of Australia since 1970. Across the same region, May to July rainfall has seen the largest decrease, by around 19 per cent since 1970.

  • In the south-east of Australia, there has been a decrease of around 10 per cent in April to October rainfall since the late 1990s.

  • There has been a decrease in streamflow at most gauges across Australia since 1975.

  • Rainfall and streamflow have increased across parts of northern Australia since the 1970s.

  • There has been an increase in extreme fire weather, and a longer fire season, across large parts of the country since the 1950s.

  • There has been a decrease in the number of tropical cyclones observed in the Australian region.

  • Snow depth, snow cover and number of snow days have decreased in alpine regions since the late 1950s.

  • Oceans around Australia are acidifying and have warmed by more than 1 °C since 1900, contributing to longer and more frequent marine heatwaves.

  • Sea levels are rising around Australia, including more frequent extremes that are increasing the risk of inundation and damage to coastal infrastructure and communities.














Global


  • Concentrations of all the major long-lived greenhouse gases in the atmosphere continue to increase, with global annual mean carbon dioxide (CO2) concentrations reaching 414.4 parts per million (ppm) in 2021 and the CO2 equivalent (CO2-e) of all greenhouse gases reaching 516 ppm. These are the highest levels on Earth in at least two million years.

  • The decline in global fossil fuel emissions of CO2 in 2020 associated with the COVID-19 pandemic will have a negligible impact on climate change. Atmospheric CO2 concentrations continue to rise, and fossil fuel CO2 emissions, the principal driver of this growth, were back to near pre-pandemic levels in 2021.

  • The rate of accumulation of methane (CH4) and nitrous oxide (N2O) (both greenhouse gases) in the atmosphere increased considerably during 2020 and 2021.

  • Globally averaged air temperature at the Earth’s surface has warmed by over 1 °C since reliable records began in 1850. Each decade since 1980 has been warmer than the last, with 2011–20 being around 0.2 °C warmer than 2001–10.

  • The world’s oceans, especially in the Southern Hemisphere, have taken up 91 per cent of the extra energy stored by the planet (as heat) as a result of enhanced greenhouse gas concentrations.

  • More than half of all CO2 emissions from human activities are absorbed by land and ocean sinks, which act to slow the rate of increase in atmospheric CO2.

  • Global mean sea levels have risen by around 25 cm since 1880 and continue to rise at an accelerating rate.













Future


In the coming decades, Australia will experience ongoing changes to its weather and climate. Australia is projected to experience:

  • Continued increase in air temperatures, more heat extremes and fewer cold extremes.

  • Continued decrease, on average, in cool season rainfall across many regions of southern and eastern Australia, which will likely lead to more time in drought, but with ongoing climate variability that will give rise to short-duration heavy-rainfall events at a range of timescales.

  • Continued increase in the number of dangerous fire weather days and a longer fire season for southern and eastern Australia.

  • Further sea level rise and continued warming and acidification of the oceans around Australia.

  • Increased and longer-lasting marine heatwaves that will affect marine environments, such as kelp forests, and increase the likelihood of more frequent and severe bleaching events in coral reefs around Australia, including the Great Barrier Reef and Ningaloo Reef.

  • Fewer tropical cyclones, but a greater proportion is projected to be of high intensity, with large variations from year to year.

  • Reduced average snow depth in alpine regions, but with variations from year to year.















On a more local level for many North Coast Voices readers........


KEY MESSAGES FOR THE NSW COASTAL ZONE IN 2030     (8 years into the future)


  • Average temperatures will continue to increase in all seasons (very high confidence).

  • More hot days and warm spells are projected with very high confidence. Fewer frosts are projected with high confidence.

  • Decreases in winter rainfall are projected with medium confidence. Other changes are possible but unclear.

  • Increased intensity of extreme rainfall events is projected, with high confidence.

  • Mean sea level will continue to rise and height of extreme sea-level events will also increase (very high confidence).

  • A harsher fire-weather climate in the future (high confidence).

  • On annual and decadal basis, natural variability in the climate system can act to either mask or enhance any long-term human induced trend, particularly in the next 20 years and for rainfall. 



The full State of the Climate 2022 biennial report can be read and downloaded at:


http://www.bom.gov.au/state-of-the-climate/2022/documents/2022-state-of-the-climate-web.pdf. - Presentation Style A


https://www.csiro.au/en/research/environmental-impacts/climate-change/state-of-the-climate - Presentation Style B


Turning to the next three months across Australia.......


Australian Bureau of Meteorology

Long-range forecast overview

Issued: 24 November 2022


December to February rainfall is likely (greater than 60% chance) to be above median for the Queensland coast, north coastal and southern New South Wales, all of Victoria, south-eastern South Australia and eastern Tasmania. Below median rainfall is likely for parts of Western Australia.


December to February maximum temperatures are likely (greater than 60% chance) to be warmer than median for Tasmania, and most of northern and western Australia. Below median temperatures are likely for south-eastern parts of Queensland, central and eastern New South Wales, parts of Victoria and the south coast of Western Australia.


December to February minimum temperatures are likely to very likely (greater than 60% to greater than 80% chance) to be warmer than median for most of western, northern and south-east Australia. Below median temperatures are likely for parts of north-east New South Wales.


This wet outlook over northern and eastern Australia is consistent with several climate drivers, including La Niña, a weakened negative Indian Ocean Dipole event, a positive phase of the Southern Annular Mode, and record warm waters around Australia. A Madden–Julian Oscillation pulse is strengthening as it moves into the Western Pacific region, which may also contribute to wetter conditions for parts of north-eastern Australia.

[my yellow highlighting]


No comments: