What exactly is the difference between climate change and global warming? Don’t hate, I’m new at this.

A certain David Weissman asked a question on twitter:

The first few answers (listed above) didn’t seem very helpful. Not to worry, David. I’m here for you.

It’s the TREND, dumbass!

Australian Heat Waves: Ode to Adelaide

What with Australia’s record-breaking multiple-heat-waves January, amidst talk of frying eggs on the sidewalk and melting asphalt and bats dropping dead because their brains cooked in the afternoon heat, we’ve looked at temperatures down under. We’ve noted overall warming, and the increase in the number of hot days. But we haven’t specifically looked at heat waves, which require multiple hot days in a row — usually, 3 or more, which is what we’ll go with.

The city of Adelaide, capitol of South Australia, has been in the news for setting a new record: hottest temperature in Australia ever recorded in a major city, at 46.6°C (115.9°F). It sounds a bit iffy to say “in a major city,” but I’ll let Adelaide have its day and look at its past heat waves.

Climate Forcing

Readers have recently discussed the correlation through time between global temperature on the one hand, and CO₂ concentration on the other. Close examination shows that the correlation is stronger during some time intervals, weaker during others, and although it’s strong overall, there seems to be a lot happening to temperature other than mimicry of the CO₂ changes.

One suggestion was to study the relationship, not with CO₂ concentration, but with its logarithm. This is because climate forcing — a measure of the ultimate climate-changing impact — is proportional to the logarithm of the CO₂ concentration, not to the concentration itself. The idea is to look for correlation between temperature and climate forcing — and it makes sense.

The fascinating thing is: there are many different climate forcings. A lot more than just CO₂.

Jiggle Room for Bigger Bull

Some are trying to defend Judith Curry’s claim that early 20th century global warming (i.e. between 1900 and 1950) was “almost as large as the warming since 1950.” An ardent attempt from Jaime Jessup reveals a mind hard at work, trying to make the evidence fit belief.

Let me explain.

Global Temperature 2018

Some organizations which estimate global temperature change have been behind schedule because of the U.S. government shutdown. But the folks at the Berkeley Earth Surface Temperature project have released their figures for December’s temperature, bringing the year 2018 to a close. It was a hot one.

Hot and Cold Curry

A post by Judith Curry discusses the “Early 20th Century Warming,” i.e. the rise in global mean temperature during the early 20th century. True to form, Curry can’t get past the first sentence without telling the kind of whopper which shows how little she understands about the topic she has chosen:

A careful look at the early 20th century global warming, which is almost as large as the warming since 1950.

Bullshit. I’ve heard this bullshit before.

Maine and Global Warming

Mainers are so lucky to live in a place free from the trials and tribulations of global warming.

Climate: Good Graphs, Bad Explanations

Regular readers know, I love graphs. I use them a lot. I tend to make them “scientifically,” i.e. the kind of graph you’d see in a scientific journal article. Just the fact, ma’am.

The Oz Heat Distribution

We’ve spoken before (as have many before us) of the fact that climate isn’t just about the average, it’s about the whole distribution (the probability distribution if you want to get technical).

We also emphasized that the tails of the distribution — the probabilities for extreme values (very very cold or very very hot, if we’re talking about temperature) can change profoundly when we shift the distribution left or right, without otherwise changing its shape; we illustrated this with July temperature in Moscow:

It set me to wondering, how do things look down under?