A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).



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The Sahara may flip from desert to grass every 20,000 years. Blame The Sun.

MIT researchers think they have solved a bit of a mystery regarding Sahara dust, but if they’re right it means the Sahara Desert has already come and gone 3 – 5 times since humans walked the Earth. The Sahara is the largest desert on Earth, and this would be the largest and longest drought “ever” on the planet (as far as we know).

UPDATED: Commenter Javier points out these drying cycles were known years ago. (See below)

This would rather redefine the whole idea of “climate change” — 3.5 million square miles of Green Sahara turns into Dust-bowl Sahara — and it’s all thanks to sunlight. The drought doesn’t just last 7 years, but more like 7,000. And it’s happening over 9 million square kilometers, an area larger than Australia. The major climate models leaned towards the monsoonal cycle, rather than the longer ice age one. So this theory may have resolved one of the 495 contradictions in climate models. Or not. But the bigger message here is that the sun causes climate change and on a massive scale.

h/t to Roger Tallbloke.

The Sahara is the largest dust bowl in the world, dumping 10 million trucks of dust across […]

Solar Wind bombardment “worse than we thought”, but we *know* particles at 800km/s have No effect on our climate

Solar Wind, Earths magnetosphere. Image: NASA

The Solar Wind is a torrent of space weather cruising past at 500 — 800 kilometers per second which is around 1.5 million miles per hour or, if you prefer, Mach 2,000.* It’s so powerful it erodes rocks on Mars, ejects particles up high and creates a kind of atmosphere of tiny rock particles which we can study. Then it blows that Martian atmosphere away.

In this new research people realized it was not just the rain of tiny high-speed protons fritzing Mars at 800 km per second that were carving up the rocks — the main role was from the heavy and highly charged He2+. (Now there’s a molecule you don’t see too often).

You might think that a variable torrent of charged particles that are constantly changing speed and direction might have an impact on our atmosphere, but you’d be wrong (or at least, politically incorrect). On Earth the solar wind “just causes the northern lights”. How do we know? We’ve got climate models. In all known GCMs the total global forcing for solar wind is “zero”. Must be true.

Thus and verily the IPCC can conclude that a flow […]

Satellite going AWOL at 28,000km/hr — tracking that Chinese stray machinery

The ESA blog has this trajectory “prediction” (below). Given that the window of reentry stretches across a day and the object in question is doing 28,000 km per hour, we can say for sure this will hit Earth. (Or rather, some small part of the satellite that survives the burning up process will touchdown somewhere). Two weeks ago Roy Spencer predicted it will probably hit “the ocean” and explained why it is so difficult to estimate the actual impact point. It is circling the Earth every 89 minutes.

UPDATE: This was China’s first space station. Launched in 2011. It has two sleeping spots for astronauts, and was visited twice. View this as a mark of the rise of China. Though it also says something that China lost control/contact with it in March 2016. Tiangong-1 is only 8,500 kg. The Russian space station Mir was 120,000kg.

UPDATE #2: 3pm Watch the LIVE track at N2Yo (overloaded) or at SATview or Heavens Above.

UPDATED #3: Narrowing the risk map. Dr Marco Langbroek‏

Aerospace estimate is April 2 at 02:00 UTC ± 7 0:18 UTC ± 2 hours. (Current UTC time is 5:10pm, so seven-ish hours to go, more or less.) USA […]

Historic Eclipse will test US solar-power grid like … clouds do

Eclipse Map: NASA

Feel the panic. Or not.

Historic Eclipse Will Test America’s Grid as Solar Waxes, Wanes

Grid operators, utilities and electricity generators are bracing for more than 12,000 megawatts of solar power to start falling offline as the moon blocks out the sun across a 70-mile-wide (113-kilometer) corridor stretching from Oregon to South Carolina.

This is the first major test of the power grid since America started bringing large amounts of intermittent solar and wind resources onto the system. It comes just as the grid is undergoing an unprecedented transformation whereby flexible resources such as battery storage will complement growing supplies of solar and wind.

Reader Andrew writes: “The path of totality is trivially narrow although the partial eclipse is quite wide. But they mustn’t have clouds in the US.”


Looks like it is being marketed as some kind of dummy run to “prove” intermittent energy will not hurt the grid when it “takes over”?

The celestial event provides an opportunity to test plants, software and markets refined in recent years in anticipation of the day when renewable energy becomes the dominant source of power.

Or perhaps it’s […]

The solar wind dumps energy into the far upper atmosphere through a kind of slow massive lightning

UPDATE: Libby Plummer at The Daily Mail has a different take, calling this a natural thermostat that cools the upper atmosphere after solar storms. I guess we’ll have to wait to see the paper to see if this can be connected to the global surface temperature at all.

The solar wind is is coming at us at a million miles an hour, but we really don’t know much about what happens when it weaves and buffets past us. In a news release NASA GISS describe how their traditional understanding of what is going on 150 miles up can sometimes just turn inside out. That’s “Revolutions in Understanding the Ionosphere, Earth’s Interface to Space”. It describes how energy from space weather can get into the ionosphere, and also muck up some of our satellites.

Despite climate models being sure that the Sun has hardly any effect, even NASA Giss admits there are some pretty wild things going on up there, and they are mostly due to the Sun. As the solar wind blasts in, it can set up a voltage difference between the upper layers of the atmosphere and the “magnetosphere”. A current will flow, discharging this energy into […]

The Solar Wind may be changing the surface temperature of the North Atlantic

Could it be the missing key? The solar wind blasts charged particles, electrons, stuff, towards Earth at 500 km a second — that’s one to two million miles per hour. It speeds up, slows down and shifts in direction as it travels past the Earth and has its own magnetic field. The wind speed varies from 300 km per second up to 800 and the impact on Earth changes with our magnetic field and our seasons. You might think this kind of monster flow might have some effect on our climate. But modern climate models are 95% certain that none of this matters. Only crazy people would think that a electrons flying past at a million miles per hour could “do something” to our stratosphere, or ozone, or cloud cover.

Curiously, a recent study shows that when the solar wind is fastest, the North Atlantic is coldest on the surface. The NAO (North Atlantic Oscillation) appears to correlate. The effect is strongest in the northern winter months. Notably the modern expert climate models fail to predict any of the cycles within our major ocean basins. How immature is our understanding of space weather?

Could changes in the solar wind be […]

Magnetic Reconnection – Major space weather effect measured for the first time

The liquid iron flowing in the Earth’s core maybe what drives a magnetic field some 40,000 km to 370,000 km out beyond the Earth. The solar field envelopes that. At the layer where these fields interact sometimes the Sun and Earth’s magnetic field lines do something called “reconnecting” — suddenly converting magnetic energy into plasma energy in an explosive way. We’ve finally just measured one event properly for the first time. So a 12,000km ball of lava with a thin crust of rocks and 15 km of damp air, floats in a sea of magnetically charged fields. You might think that our slithery-thin layer of humid air and clouds could be affected by the stirring of “yo-yo” like lava flows and magnetic fields that are also twisted by solar dynamos, but you would just be a silly denier. These magnetic explosions and solar winds can’t possibly affect our climate — there’s a 97% consensus that says so.

Luckily we have climate models that are 95% certain we don’t even need to include these factors — especially lucky, since we barely understand them.

This is after-all, just space weather, and it’s not like the Earth is in space, eh?

Supposedly geomagnetic […]

Extreme solar storms hit Earth in 774 and 993AD — What would happen if one hit now?

August 31, 201. This coronal mass ejection just missed Earth, according to NASA

There were two mysterious sudden spikes in carbon 14 in tree rings around a thousand years ago. Now some researchers at Lund University say they’ve matched those to beryllium layers in ice cores from the Arctic and Antarctic. Some wild event made these changes across continents all over the world at the same time, and about the only thing that could have done that was a massive solar storm (or two). There are estimates these extreme storms would have been ten times stronger than the biggest solar storms we have had in the last few decades. The two big bad storms are described as a few times bigger than even the largest solar storm in modern history, which was The Carrington Event in 1859. The radioactive spikes specifically show up in tree rings in 774/775AD and 993/994AD. It’s pretty cool that we can pin those years down so accurately, and as an aside, I imagine it makes a fairly handy calibration point for tree ring researchers now that we know it was global.

Unfortunately, if one of those happened now, it would not be fun. The […]

Solar activity was really at exceptional lows during the cold Maunder Minimum

Fig 3 (Part VI only) Sunspot drawing of by G.D. Cassini in 1671 (Oldenburg, 1671c).

What is surprising is just how much data we have on the Sun from 400 years ago.

For some aspects of solar activity we barely have a half a solar cycle. For example, on solar spectral changes: UV and Infrared light swing up and down through the solar cycle, but we only got a good grip on these important changes in the last ten years with the SORCE mission.

But on other aspects of solar activity there is much more long term data than I expected: 400 years ago quite a few people were carefully recording detailed drawings of sun spots (like Cassini in 1671, right). Others were reporting aurorae — up to 150 a year in parish records, newspaper reports, and scientific observations, which tells us something about the strength of the solar wind. There were also observations of the solar corona during eclipses at the time, which suggest the sun was less active as well.

Lately some (Zolotova et al) have said solar activity was not low during the cold Maunder Minimum period from 1645 – 1715. Usoskin and others have responded […]

Earth creates tides in the rock that is the Moon

Earth from the Moon | NASA

Thanks to the Earth’s gravitational pull, the Moon is slightly egg shaped. The closest part bulges out by 51cm towards the Earth, and here’s the weirdest thing, the bulge moves. The same side of the Moon always faces Earth, but if you stood on the Moon, the Earth would appear to wobble around a particular patch of “moon-sky”. And like a tide of rock, the bulge in the surface, slowly rolls around on the Moon — following the pull from the Earth.

The ball of rock called the Moon is 3,474 km in diameter. I’m guessing the Man-on-the-Moon would not notice the tide much.

Though I imagine it will be a right headache for future Moonville Skyscrapers.

Despite the force required to deform a ball of rock that large, and from such a distance, climate models in their infinite wisdom know that the science is settled and the Moon has no significant effect on Earth.

You might recall that Ian Wilson has other ideas, and suggests lunar cycles set up atmospheric standing waves which may seed ENSO patterns.

And we wonder why those models don’t work?

8.4 out of 10 based on 59 […]