Archive for the ‘Climate Sensitivity’ Category

Nova misleads on Scafetta’s cycle of mistakes

October 12, 2013

Joanne Nova leaps at the chance to blame the sun for the recent warming. In the process she shoots her own foot on the Medieval Warm Period, then shoves it in her mouth on Climate Sensitivity. Oh, and the paper is just another example of curve fitting crap.


Fingers In Ears

September 3, 2013

With her digits firmly planted in her ears Joanne Nova pretends that AGW is not happening. The science says otherwise. Perhaps Jo is too busy with Tony “It’s crap” Abbott’s political campaign to write about the science, or perhaps it’s just because these climate science papers don’t agree with her preconceived, politically motivated, scientifically-unsupported, blogger opinion? Here’s a small sample of recent peer-reviewed science Joanne wants to wish away.

update: Nova has commented on this list saying “I can rebut most just from their headlines.” … but of course she doesn’t go any further than that and instead yet another person gets “moderated” when the topic becomes too much for Nova. Joanne repetitively points to her “Evidence”, a page which we’ve covered in detail .


Climate Sensitivity (the short of it)

May 23, 2013

A new study suggests short term warming will be less, but long-term warming to remain about the same.

Joanne Nova gets all excited about the prospect of less short term warming that she forgets that (in her opinion) models are 100% wrong. She also chooses to ignore the authors comments about long term temperature forecasts remaining unchanged.

Cherry picking the bits of a report she like is what Joanne Nova does best.


Hot Spot 2 – Tropospheric Warming Continues

February 11, 2013

Hotspot Found!

… by Nova. She just didn’t realise it.

Often you will hear Joanne Nova comment about the “missing hotspot” as if  this were evidence against global warming. It’s not. This has been addressed numerous times (1, 2, 3, 4, 5, 6, 7, 8).

Here we examine each of her posts (tagged as Hot Spot) and explain why they are incorrect or misleading.


Oh, that Heatwave? It could be Aliens!

January 28, 2013

Nova repeats her strawman argument that the recent heatwave is not a sign of global warming.

Climate Scientists go to pains these days to explain that you cannot attribute one weather extreme on global warming, but you will see a higher number of heatwaves as the background climate becomes hotter.

In Australia, we are now breaking hot records three times more often than cold records. It’s simply more likely for heatwave, such as the January one to occur.

Nova doesn’t get math, so instead rambles out 8 “Nova reasons” why the recent heatwave is not because of global warming.


Nova Lacks Evidence

January 1, 2013

Joanne Nova claims that Global Warming has been disproved and lists 9 “Major Flaws” – or so she says.

  1. The missing heat is not in the ocean.
  2. Satellites show a warmer Earth is releasing extra energy to space.
  3. The models get core assumptions wrong – the hot spot is missing.
  4. Clouds cool the planet as it warms.
  5. The models are wrong on a local, regional, or continental scale.
  6. Eight different methods suggest a climate sensitivity of 0.4°C.
  7. Has CO2 warmed the planet at all in the last 50 years? It’s harder to tell than you think.
  8. Even if we assume it’s warmed since 1979, and assume that it was all CO2, if so, feedbacks are zero — disaster averted.
  9. It was as warm or warmer 1000 years ago. Models can’t explain that. It wasn’t CO2.  The models can’t predict past episodes of warming, so why would they predict future ones?

It’s the usual stuff from Nova, so lets take a quick look at why Nova is wrong on all nine points.


Nova’s Dryspot

December 7, 2012

Recent research by Fasullo and Trenberth (covered here by SkS) showed that climate models that do a better job at reproducing observations of humidity, are also forecasting a higher sensitivity (greater warming).

Models that better simulate humidity near the infamous hotspot that Nova harps on about, suggest that the warming will be at the higher end of current estimates.

Joanne Nova wants nothing more than to discredit the models, and finds opportunity in John Christy’s blog post. Yeah it’s not peer-reviewed science, of course, but let’s take a look anyway at Christy’s folly.


Last 30 years shows … Nova can’t learn

April 11, 2012

Once more it seems necessary to remind Nova of what Climate Sensitivity why it’s invalid to compare equilibrium expectations against non-equilibrium measurements that are influence by more than just CO2 levels.

Nova compares the last 30 years of warming against her concept of what we should have expected. The problem is she forgets the definition of Equilibrium Climate Sensitivity, the influence of a cooling sun, and the impact of aerosols.


Climate Sensitivity – Idso? Idsnot!

April 2, 2012

Climate sensitivity is defined as

a measure of how responsive the temperature of the climate system is to a change in the radiative forcing.

Nova’s recent claim on this topic is the use of Sherwood Idso’s research from the 1980’s. Idso’s research was scientifically debunked because his calculation did not actually equate to that of climate sensitivity (see below). No climate scientist used Idso’s methods to determine climate sensitivity because, as we’ll examine, his mistakes were obvious, measuring the change in surface radiation rather than top of atmosphere, measuring the changes in one small location, then extrapolating that to the whole planet, measuring apparent changes in Mars and expecting the Earth to respond in a similar way, not allowing time for equilibrium to be reached.

The most obvious reason why Idso’s estimate of 0.4°C rise in temps for a doubling of CO2 is too low; the planet has warmed that much since he first published in 1984, whilst CO2 levels rose 15% from 350 to 390 ppm.


Carbon dioxide is already absorbing almost all it can – really?

March 8, 2012

On the list of debunked myths that “skeptics” like to promote in an attempt to downplay the significant role of CO2 as a greenhouse gas is the old “More CO2 has little effect” card; Nova’s no exception with her “Carbon dioxide is already absorbing almost all it can” post. This has been debunked many times over. Interestingly in the early 1900’s it was a valid skeptical argument, but it was rebutted and ever since climate scientists knew better.

That doesn’t stop political bloggers from dragging out old myths. Nova goes on to confuse the issue even further.