Statements on the warming climate are supported by two main research approaches: observation and modelling.

Observation: It has long been diagnosed that the Earth has a fever, and some latest measurements and facts are alarming:

  • 2015 was the hottest on record globally;

  • January 2016 was the hottest month on record globally (link);

  • February 2016 had record warmth in the atmosphere globally (link);

  • In Australia, 2015-2016 summer temperatures were the top ten warmest on record, especially that Tasmania – the most southern state of Australia closest to the continent of Antarctica – experienced its warmest summer since records began (link 1link 2).

Given the current warming trend, one may wonder how hot it will be in the future, say in 2050 or 2100. This is where climate modelling has its unique and best place.

Modelling: We explore the new NASA Earth Exchange Global Daily Downscaled Projections (NEX-GDDP) dataset (link) and take Australia as an example for this discussion. As the dataset is large (~12 TB) involving the outputs of 21 global climate models (including CSIRO-MK3.6.0 and ACCESS1.0 climate models from Australia), we have developed automated routines for analysis and mapping. The results in the form of maps may be more accessible to the general public and an example is shown below.

Average daily maximum surface temperature by February: That is, daily maximum surface temperatures are averaged by the month of February. Figure 1 below shows the temperature increase of at least 2 degrees Celsius for the overwhelming majority of the continent from Feb. 2000 (historical) to Feb. 2100 (projected), based on the CSIRO-MK3.6.0 Climate Model from Australia. 

Figure 1: The increase of average daily maximum surface temperature (by February, in degrees Celsius) across Australia from Feb. 2000 (historical) to Feb. 2100 (projected), based on the CSIRO-MK3.6.0 Climate Model under a moderate greenhouse gas emissions scenario known as Representative Concentration Pathway – RCP4.5. Data source: NASA Earth Exchange Global Daily Downscaled Projections (NEX-GDDP, 2015). Analysis and mapping:, 2016.

Also note the following two points:

– It is well known that climate models have some uncertainties, but their ability to project a warming trend over a  large territory has been consistent.

– What has been analysed and mapped is just the increase of monthly mean temperature, and given climate variabilities one can imagine there would be many more days with extreme temperatures and heatwaves in the future.