The power of spin

8 02 2015

It’s highly likely that most readers of this blog will have seen this image.  It’s doing the rounds all over the internet, not least Facebook….:

desert-eumena

I haven’t checked the veracity of the size of the squares, but for the sake of argument, let’s give the creator of this spin the benefit of doubt.

Escondida Mine in Chile

Escondida Copper Mine in Chile

To build a solar farm of any size, resources have to be dug up out of the ground.  All sorts of mineral ores, copper, iron, aluminium, silicon, oil for wire insulation, rare earths, cement for concrete footings, the list will be long.  Mining ores are now getting lower and lower in concentrations as we reach limits to growth.  Some are mere tenths of 1%, while iron ore is much better, with some reaching an amazing 60% concentration!

Aluminium ores are more like 7.5%, whilst the average grade of copper ores in the 21st century is below 0.6 percent Cu.  That means gigantic holes like that at left have to be dug to achieve the squares in the Sahara as shown above….

I contend (without doing the necessary research I don’t have time to do – and I can see a PhD thesis for someone here!) that to build the desired solar stuff inside those squares in the Sahara would entail digging huge holes 2 to 10 times as large as the squares to make the panels and associated electronics; not to mention the power lines to distribute the electricity far and wide.

The damage done to build this stuff just so we can ‘have our cake and eat it’ is mind boggling. And of course there are also the emissions of greenhouse gases generated while mining and manufacturing which have been discussed here ad nauseam in earlier posts…..  The power of spin is such that the uninformed will continue believing we can have it all, only solar powered.  We just have to fill those squares in North Africa, and everything will be cool…..





Climate models in perspective

8 02 2015

Mark Cochrane

Mark Cochrane

Another guest post from Mark Cochrane.

One of the favourite refrains from climate change ‘skeptics’ is saying that models are wrong, which is a bit like saying that water is wet. Models are simplifications of more complex systems and as such they are always going to be ‘wrong’ but the question is whether or not they are useful. Weather models are wrong too but we use them all of the time. Sometimes they over predict precipitation or temperature while at other times they under predict.  The Weather Channel actually uses ‘proprietary methods’ to over predict the chances of high precipitation (link), presumably because they’d rather be wrong in one direction than the other.

The ‘skeptic’ claim is that climate scientists do something similar with their projection of future climates for a range of probable emissions scenarios. Somehow hundreds of scientists across multiple groups all manage to collude in this mass delusion to make us worry more than we should about the future impacts of our fossil fuel dependent culture.

Favorite climate skeptic Christopher Monckton and colleagues recently published an article (link) saying as much in the somewhat obscure Chinese journal Science Bulletin. I’ve never heard of this journal before but they are making an attempt to be in the peer-reviewed literature so I won’t quibble. They make the case that the IPCC model scenarios are overstated by a factor of 2 or 3. If you want an in depth summary and critique of this paper see this blog post. Relative ranking of journals is often done using their respective Impact Factors; their likelihood to yield citations to any given work. Scientists aim to get their works into the best location for their work to be read and used by their peers. Science Bulletin has an impact factor of 1.4, Nature has one of 42.4.

Now an analysis has been done to test whether model misses of the so-called warming ‘hiatus’ are due to having incorrect model forcing (sensitivity to greenhouse gasses – e.g. CO2) or other random factors (mostly volcanoes and ocean modes – e.g. El Nino etc.). The paper in Nature by Marotzke and Forster (2015) does this by comparing model simulations used by the IPCC and observations of global mean surface temperature as functions of all possible 15-year (and 62) trends from 1900 to the present.

An in depth explanation of the paper can be found here.  The use of 15 years is somewhat arbitrary but it provides a test of using short time periods to get whatever trend is desired. If the nefarious climate scientists are really making their models over predict the rate of warming then when you plot all of the differences between the model outputs and the actual observations they would tend to be greater than zero. This is the pattern you see from 1998-2012 (middle below), the period of the so-called hiatus or pause. However, you see the exact opposite pattern from 1927-1941 when models would have been accused of seriously under predicting temperature increases (left panel below). When you plot all of the data (right panel) the results are not significantly biased either way.

Comparing model-simulated (brown bars) and observed global surface temperature (vertical black line) for the 15-year periods covering 1927-1941 (left) and 1998-2012 (middle), and for all 15-year periods between 1900 and 2012 (right). Source: Marotzke and Forster (2015)

The models are not systematically biased in either way, they just cannot account for chaotic or random factors within the atmosphere and ocean. Therefore they will seem to over predict and times and under predict at other times. Where are we now?

Still cruising along the lower portion of the 95% range of the model simulations. If it were a blood test you still wouldn’t have a little asterisk on your test but it would be close.

It is noteworthy that this apparent inaccuracy only pertains to ‘surface temperatures’ of the Earth. There are no indications that the rate of warming has actually slowed down in any way. The only change has been in the amount of energy being stored in the world’s oceans. Despite our terrestrial surface bias of measuring the climate, over 90% of the energy is piling up in ocean waters, with much of the heat being transported into deep reaches (>700 m) as chaotic processes lead to periods of ocean water turnover.

The wiggles in the ocean uptake (blue above) of heat end up as periods rapid warming or a ‘pause’ these days in surface temperature. Note, back before 1970 those down turns would cross beneath the land component and yield actual global cooling for short periods. Ocean processes call the tune of energy transfer and the atmospheric and surface temperatures dance to it on short time scales. None of this changes the steady ramp of ongoing energy storage in the long term trend due to green house gas accumulations that is driving global climate change.