Australia’s overall national heat record was smashed the past couple of days, with the hottest recorded day being topped by a full 1C increase the following day (December 19).
If it was just Australia getting hotter you could shrug it off, but it is getting hotter around the world, including in the oceans, just as global warming science predicted decades ago.
Worryingly, heat records are falling despite the fact the sun is at a solar minimum in its regular 11-year cycle.
The graph at the top of this page shows solar activity since 2008.
Sunspot numbers tend to go up with solar output.
Soon, solar output will increase with the next solar maximum, which is expected around 2030.
Solar output does not change much within these cycles, but it will likely have some effect.
Often quoted in arguments about climate change are Milankovitch cycles, which are patterns in the earth’s movement around the sun.
Milankovitch cycles don’t explain anything with certainty, but they do show that past changes in earth’s climate far exceeded that what should be caused by the slight changes in the earth’s movement around the sun.
This suggests that the earth’s climate is finely balanced, and that once shifted, feedback loops kick in that change the climate far more than the actions of solar input.
For an example of feedback – heat melts permafrost, which puts more greenhouse gas into the air, which melts more permafrost.
As I have noted earlier, this may already be happening, with methane going up fast at Barrow, in the Arctic.
Other things may help accelerate climate change, such as removing sulfur from shipping fuels, as reported here.
Ironically, anything that removes particulate pollution from the air allows more sunlight to hit the earth, and the loss of this “global dimming” is a conumdrum for those who want to close coal plants etc.
With heat records falling, and likely to keep falling, it is a very good time to be living in Tasmania.
Read more about solar cycles here, and Milankovitch_cycles here.