Climate change - Greenhouse Gas emission data is absolute and unambiguous

Figure A

Note to Figure A: Climatic response time series from 1979 to the present [IPCC data] The rates shown in the panels are the decadal change rates for the entire ranges of the time series. These rates are in percentage terms, except for the interval variables (d, f, g, h, i, k), where additive changes are reported instead. For ocean acidity (pH), the percentage rate is based on the change in hydrogen ion activity, aH+ (where lower pH values represent greater acidity). The annual data are shown using gray points. The black lines are local regression smooth trend lines [authors William J Ripple, Christopher Wolf, Thomas M Newsome, Phoebe Barnard, William R Moomaw et al].

In November 2019, a call to action was issued by 11,258 scientists following the publication of new data (in the professional journal, Bioscience) demonstrating rising greenhouse gas (GHG) emissions, global temperature increases with a range of corresponding impacts on the planet. This is not the first time such an unequivocal message has been delivered with a similar one being issued in 2017 but alas, insufficient action and business-as-usual has continued. Of particular concern -

• despite solar and wind energy consumption increasing by 373% per decade, it is still 28 times smaller than fossil fuel usage
• fossil fuel subsidies continue to energy companies and amount to a staggering US $400 billion in 2018
• the three abundant atmospheric greenhouse gases (CO2, Methane and Nitrous Oxide) continue to increase:  CO2 by 4.98%, Methane by 3.65% and Nitrous Oxide by 2.46% over the previous 10 year period
• global surface temperature has been increasing by 0.183C over the ten year period and faster than had been previously predicted
• ice has been disappearing: Arctic sea ice decreased by -11.7%, Greenland ice mass by -2610 gigatonnes, Antarctic ice mass -1230 gigatonnes
• ocean heat and acidity has increased with acidity by +4.12%

Depite the 1992 Rio Summit, the 1997 Kyoto Agreement, the 2015 Paris Agreement and numerous UN COP meetings, there has been insufficient action and progress with decarbonising or moving to low carbon renewable energy sources.

The articles can be accessed at these links -

Bioscience article 2019 World Scientists' Warning of a Climate Emergency

Bioscience Vol 67 No 12 2017 World Scientists Warning to humanity

Public perceptions about climate change - the good, the bad and the ugly

Diagram 1

The climate change issue is as complex a topic with global community engagement and communication as much as it is about the science and technological solutions to address it. While there is strong support for action in Europe, the Pacific and many parts of Asia, there continues to be very divided opinions in the United States and Australia.

The Yale Program on Climate Change Communication has provided valuable insights into the communication challenge with climate change and the US population. Flowing from research and survey work started in 2009, the Yale program has demonstrated that there are six distinct and unique audiences in the US.  These six audiences have very different levels of engagement on the climate change issue due to varying psychology, culture,  risk perception, attitudes and political affiliation.

The Alarmed  are fully convinced of the reality and seriousness of climate change and are already taking individual, consumer and political action to address it. The Concerned are also convinced about global warming but are not engaged with it personally.

The three other groups being the Cautious, the Disengaged, and the Doubtful represent different stages of understanding and acceptance that climate change is a problem. None of these groups are actively engaged with the issue.

The real concern are the Dismissive who are very sure that climate change is not happening and are actively involved as opponents of a national effort to reduce greenhouse gas emissions.

The distribution and size of the six groups are shown in Diagrams 1 and 2.

There are signs that perceptions are changing and that public opinion in the United States is slowly shifting to greater engagement and concern about climate change. Comparing Diagram 1 (above) with Diagram (2) below which covers a 12 month period from 2018-2019, a discernible movement to greater alarm can be detected.

Diagram 2

From an Australian point of view, similar categories of community engagement would almost certainly be identified here with key political leaders being within the Dismissive group.

Link to the Yale study -
Yale climate communication - global warming

Understanding the impact of climate change on direct weather events

In late 2019, one of Australia's major commercial insurance companies, IAG, in collaboration with the National Centre for Atmospheric Research in the United States, released  a report outlining the increased severe weather which will occur as a result of climate change. The report models impacts at 1.5C, 2C and +/- 2 degrees Celsius and makes for better understanding of the direct weather events caused by climate change rather than the larger global impacts of melting polar ice, acidification of oceans, higher temperatures and mega storms.

The report should probably have garnered greater interest at the time of release given it was commissioned by a large commercial insurer. The overall tenor of climate debate in Australia and political dynamic would not have been conducive to ensuring it received sufficient attention.

Of note, IAG's perspective is "... the level of knowledge has now reached the stage where it is possible to make confident assessment of the impacts of climate change at larger scales and longer time frames with objective assessment of the associated levels of confidence.."  This, of course, contradicts those political naysayers who believe the evidence of climate change is still contestable.

The report provides key six assessments which are summarised briefly below and given events of the past few months, many of these assessments have been shown to be accurate -

1. While the frequency of named tropical cyclones in the Australian region, the proportion of the most destructive tropical cyclones has increased at the expense of the more weaker systems. Tropical cyclone risks are therefore expected to increase rapidly in south-east Queensland,  north-east NSW regional followed by coastal districts in Western Australia.
2. Intense short duration rainfall is expected to increase almost everywhere in Australia , resulting in more frequent flooding in urban areas and in small river catchments.  
3. Areas of large hail (2.0-4.9cm in diameter) and giant hail (>5.0cm in diameter) should progressively move southwards with a large increase in the risk to the regions inland from the Hunter River, southwards through the central and southern highlands of New South Wales and central to eastern Victoria.
4. The multi-day impacts of east coast lows on the south-eastern seaboard of Australia are expected to increase due to wind-driven rainfall ingress, flash and riverine flooding. 
5. Bushfire risk, as measured by the trends in fire danger indices is likely to increase in all locations nationally leading to more frequent and extreme events and longer fire seasons.
6. Sea level rise is expected to accelerate around the Australian coastline but at differing rates. It is notable that past assessments of sea level rise are lower than those that recent observations show.

In light of actual recent new data, the IAG report may yet prove to still under-estimate the full weather impact which will be felt sooner rather than later.

The report can be accessed at this link -
IAG - NCAR Severe weather in a changing climate report

Climate change - global temperature rises since 1860

Temperatures since 1860 have increased in heat with considerable movement upward from 1940 onwards with this trend line projected to continue for the next two to three decades unless action is taken to reduce Greenhouse gas emissions.

Australia since 1970 - less water and increasing droughts

Time-based data evaluation and mapping by the Bureau of Meteorology starkly demonstrates the historical pattern of less rainfall over the Eastern half of the Australian continent which has occurred over the past 40 years. The Eastern half of the continent, comprising the states of  Victoria, New South Wales and Queensland, produces most of the agricultural outputs whereas the Western half of the continent is semi-arid, arid to desert and cannot support food production. The impact of less rainfall will be continue to be an acute problem and one which requires faster adaptation than is currently the case. 

Australia's temperature increase since 1910

Australian Bureau of Meteorology

As the bush fires have caused an indelible impact on Australia during 2019 and 2020, the actual temperature data for the continent demonstrates the  extent of the increase of temperature particularly over the past forty years. This situation matched with lower rainfall, provides the perfect vector for widespread fires on the landscape.

NSW Rural Fire Service - prediction map for 4 January 2020

The NSW Rural Fire Service (RFS) map portrays the manner in which bush fires can spread and the scale of movement given specific climatic conditions, in this case extreme temperature and wind condition.