to be sceptical about man made climate change

[Brioche201]

.. to a layperson like myself the evidence does not seem robust (record antarctic ice caps) .Even if it were true 'the climate' is such a complicated thing affected by thousands of factors.Is it likely that changing just one or 2 of the factors that are within out control would make a difference (or even that the difference would be in the right direction)
Do you still believe in man made climate change or think it is mainly rooted in politics?

Cote - well I shall refrain from giving you my qualifications to talk about electricity for fear of outing myself but can we agree that supply and demand has to be equal at all times to maintain grid stability and that Kirchoff's Law determines the individual power flows on each transmission line in an interconnected grid? Lets not get into reactive power, voltage drop and thermal limits shall we?

If so, then you must agree that when your local wind farm stops generating there must be another power station somewhere on the grid switch on and start producing to pick up the load.

Come on even a City analyst can cope with that concept.

If so, then you must agree that when your local wind farm stops generating there must be another power station somewhere on the grid switch on and start producing to pick up the load.

Well, no. It doesn't need to be switched off, it just needs to have available capacity.

And it certainly doesn't need to be fossil fue based.

Jassey - if the physical capacity is available the supply of fuel fed into the boilers (coal) or turbine (gas) needs to be either switched on or if on already the rate of fuel input increased.

Nuclear plants do not load follow. Some hydro may be available but in the UK and most of Europe it is coal or gas that does the load following - even in France has hydro and coal stations operating on the margin. France may also import power from neighbours to meet demand which almost certainly will be power from a coal or gas plant at the margin.

Actually I just checked, and I was wrong. Nuclear plants are routinely used in load-following mode in France.

Free, like you I didn't think nuclear plants load-followed anywhere. I've just had the grace to admit I was wrong, will you do the same?

There isn't a strong economic advantage for a nuclear plant to load-follow as it saves them nothing to reduce capacity (as most boiling water reactors can do), but they can do it, and it's widespread in France.

Apparently Unit A at Biblis, for example (Germany) is designed to scale betwen 40-100% at 15% a minute.

Cote - I owe you an apology for muddying the waters.

We are probably seeing the effects of climate change in the UK already

Indeed.

A few weeks ago, I was wearing white converse and trod in dog poo. I was completely unable to locate a convenient puddle IN MANCHESTER in which to rinse my soles. I had to do it with a bottle of San Pellegrino in the loo at work.

Here's something you might not know [wonder why that is...] - polar ice caps are not receding:

www.forbes.com/sites/jamestaylor/2015/05/19/updated-nasa-data-polar-ice-not-receding-after-all/

I actually quoted the original NASA article earlier on. Maybe you'd care to read it.

Lweji : not intended to steal your thunder! I wasn't going to read through all 27 pages on this thread, so missed your post whilst skimming through! Apologies!

Not a matter of stealing thunder.
It's that what NASA reported it's not quite the same as the icecaps are fine and there's nothing to worry about.

That Forbes article is by a notorious climate change denier who has, IIRC, a marketing background.

I don't know why anyone would quote Forbes when there are good, accessible sources out there easily understandable by the lay person - the NSDIC does a monthly bulletin on sea ice, for example.

In reply to the Forbes article:

<a class="break-all" href="https://www.google.pt/url?sa=t&source=web&rct=j&url=www.atmos.illinois.edu/~wlchapma/Forbes.article.response.pdf&ved=0ahUKEwijwpzw6dvJAhWLBBoKHYHIB7UQFggsMAY&usg=AFQjCNHULEXrK05dxJEkGHOQFdaZRYlllw&sig2=fPx8LwE4reTYRoUG5ZX-zw" rel="nofollow" target="_blank">reply by Illinois atmos

Washington Post comment about how you shoukd worry about melting polar ice in general

Whether it's man made or not, with 7 billion people on the planet, it's not like those in the less affected areas are just going to shuffle over and let climate refugees in. Then things really kick off.

Jassey - France has a bizarre and extremely uneconomic policy of relying on high cost nuclear power. French energy policy is to prevent as far as possible the introduction of an open competitive European electricity market. It did this by preventing for example the building of transmission lines across the Pyrenees to stop Spanish generators selling electricity to French industrial users.

France has pushed hard for the introduction of the EU Emissions Trading System to load costs on fossil fuel generators and heavy industry in other countries in an effort to make them uncompetitive against French EDF nuclear electric and French industry. That is why the French Prime Minister was so supportive of the latest COP initiative. France wants legally binding targets to force costs onto other countries. It nearly broke the EU when Germany and France argued over the EUETS.

The support for this COP initiative by France is wholly political and nothing to do with the climate at all. France is highly socialist in its economic policy and its electricity industry is one of the most uncompetitive in Europe when the full cost of building nuclear stations is taken into account.

The fact France builds and then runs its nuclear plants in a wholly uneconomic way, part loaded, is completely at odds with how British Energy and other nuclear operators around the world operate. That is baseload all the time. France is an extreme example of the 'socialist' policies and intent that sits behind the whole global warming/COP/ carbon reduction circus. It is designed to put he dead hand of Govt in charge of economic decisions and move away from markets.

I'm not disagreeing on the economics of French energy policy. However, that wasn't what you said. You said nuclear plants do not load follow, which turns out to be untrue, and not just in France.

Shall we agree we were both wrong on that one?

Your characterisation of the CoP process as 'French' and designed to suit France is naive and uninformed at best. Unless you think the 1992 treaty was designed with a 2015 presidency in mind?

I had to do it with a bottle of San Pellegrino in the loo at work

Poor show, Maidofstars - surely you realise it contains carbon dioxide??

Adaptation was a big point of discussion at the CoP. It's not as media-friendly as mitigation targets though...

*Jassey - nuclear power stations do not load follow when following normal rational rules of economic dispatch. Any power station of any type can physically load follow in the sense they can be switched on and off or run part loaded. No sensible utility would however do that with a nuclear power station though - its actually the worst type of power station to do it with. EDF do it only because of French nuclear policy. Nobody else does.

Biblis closed in 2011 and no longer operates.

You'll appreciate that people may have become confused about your meaning when you suggested nuclear was not able to scale up or down quickly in your earlier post.

The economics depend on your decisions on what the optimum mix is - which is in turn dependent on dealing with the market failure whereby the ongoing costs of gas and coal are not covered by the price. Yes, there's no immediate financial advantage to nuclear scaling down as there is to coal or gas - but that isn't the full picture of costs, is it, as many of the costs of fossil fuel production are borne by the state or by businesses and individuals.

Once you price in the impacts of air pollution and climate change, coal and gas don't look quite so cheap.

relying on banks of diesel generators, spewing out pollution and CO2 , for when the sun doesn't shine and the wind doesn't blow
is madness in my opinion.

we should invest in more baseload. whether coal, gas or nuclear, so long as its not subsidised, I don't really care.

It's all subsidised. Only some of the subsidies are hidden.

Jassey - "Once you price in the impacts of air pollution and climate change, coal and gas don't look quite so cheap."

That is the essential question that the recent COP meeting and in fact none of renewable energy lobby want to discuss.

What is the present value cost of future climate change? The climate change ad renewable lobby say that climate change is a certainty and the impact will be so severe we should spend any amount of subsidy replacing all fossil fuel use by 2050 no matter what the economic burden.

What people like me say is the science is not settled, there is uncertainty about whether climate change is man made and even if it is we don't know what the impact will be and over what timescale. The more uncertain and the further away into the future the impact (if any) will be then the less we should spend today. I assume you agree with discounting future costs to present value and that the greater the uncertainty the greater the discount rate?

The position I have is that yes we should spend money on basic R&D in universities but we should not subsidise the technology so it can be built today. If as we go into the future the uncertainty over the impact and timescale is reduced then we spend money on adaptation and on installing zero carbon technology.

Loading subsidies on renewable technology or loading taxes onto hydrocarbon fuels is a way to force the adoption of renewable technology. The question is how much we do now. You want to impose such a high cost now that renewables replace all hydrocarbon as quick as possible. I say wait and do it in a sensible way by replacing coal now with CCGT and do more later when alternative zero carbon technologies are more viable and able to stand on their own without subsidy albeit with either some carbon tax or a stringent cap and trade scheme in place.

We can reduce carbon emissions to zero now by shutting down the global economy but that is not sensible and yet that is how the global warming and renewable lobby talk at times.

FreeWorker - re "What people like me say is the science is not settled, there is uncertainty about whether climate change is man made"

There is no uncertainty. There is a near-perfect consensus that climate change is at the very least exacerbated by human activity, mainly due to fossil fuels. There are very few voices of dissent and it seems at least some are for sale.

"we don't know what the impact will be and over what timescale."

We do have a fair idea about the impact. Does the timescale matter that much? If we don't take steps now, does it matter if disaster strikes our children, grandchildren, or great-grandchildren?

"I assume you agree with discounting future costs to present value and that the greater the uncertainty the greater the discount rate?"

Discount rates have to do with expectations of future interest rates, not probabilities! Can your argument get any more clueless?

And discoun

FreeWorker as soon as you say "the science is not settled" it's plain that you're approaching this from an ideological POV not a scientific one.

The basic science of global warming was established by Arrhenius over a century ago ... and while there is still considerable uncertainty about certain aspects of climate change (like the precise value of climate sensitivity to a doubling of CO2) the fact that recent warming is anthropogenic is settled science. (The broad scientific consensus is that without increases in CO2 the world would be in a slight cooling phase).

What to do about it is of course open to debate; this a political and economic issue, not a scientific one. It seems to me given your contributions that you are quite qualified to discuss some of the technical and economic aspects of mitigation, but that you are rather unqualified to discuss the underlying science of climate change (as are most of us on this thread; I have an earth sciences background but I wouldn't pretend to be qualified as a climate scientist).