主播大秀

Now that they've called a "drought" (even though it's not), it means we'll have an awful summer.

I suppose they're calling it a "drought" to het up the climate chaos clowns.

Why is 2 years of below average rainfall not a drought? Do you have a better desription/definition?

"Why is 2 years of below average rainfall not a drought?"

So we're in drought every 4 years? I'd suggest it should be much less often than 1-in-4 given how catastrophic some journalists try to make it round when it inevitably comes around.

Denying global warming and denying the drought. Maybe your world is flat, pixies live in your garden and Martians steal your cattle.

We have noticed the effect of much less rain than usual on our allotment for the last two years. We have only managed reasonable crops by much more watering than usual. Last summer was fairly overcast, so the rain that did fall kept the ground moist for a bit longer than if it had been hot sun. If we get drying conditions this year we may need even more water. Lets hope the pixies and Martians leave our vegetables alone.

EYChris. What on earth has the current low rainfall in the south and east got to do with "global warming"? Try a weather pattern with persistent Azores high pressure ridging NE. That's all there is to it. I should buy a brolly pdq now that we have a hosepipe ban!

@Fudsdad, the connection was in comment 1, I didn't make it, it just made me laugh. Not exactly ROFL, more a sad chuckle shaking my head.

This side of the country has always been known as the drier side of Britain, indeed LNER used it in a marketing campaign on their railway posters.

What I can't figure out is why, after 1976 and subsequent low rainfall years up to present day, there has been no change to the planning regulations for new build properties to enforce some form of grey water system to be incorporated. Using shower water or washing machine water to flush a loo or water the lawn isn't rocket science is it? There is so much clean water used which goes straight back into the sewers that it's no wonder with increasing populations in these rural areas that we're running out of what little water we get over here.

If we used the water more efficiently, we wouldn't be in this situation. A new build is the ideal time to fit a grey water system rather than having to retrofit one into an existing property. If new houses since 1976 had been built with them, the problem would be a lot less than it is now.

If you're interested, here's a link to the LNER poster used between 1923 and 1947... during the height of the global warming debate ;)



I've been thinking about this a little more too. Not only has the population increased on the Eastern side, our use of water has changed even since 1976. I remember my dad having his weekly bath which was only filled to a shallow depth because the hot water tank only provided so much hot water, mum had a twin tub washing machine, dad used a bucket to wash his car, the pots were washed in the kitchen sink. Nowadays we have automatic washing machines, dishwashers, power showers, as much hot water as you need whilst the hot tap is turned on, jet washers cleaning patios and bricked driveways down and automatic car washes and a huge increase in the number of cars per household. Add all that to more people in the same area and it's asking for trouble.

Last year Yorkshire Water 'only' managed 拢320 million profit down from 拢376 million the previous year. Poor old Anglian Water managed 拢709 million.

71% of average is hardly a drought but more a failure of infrastructure. I wonder why?

"71% of average is hardly a drought" - exactly. But according to some that makes us denialist scum. It's a shame just how brainwashed they are.

Several of the main consequences of a drought are listed Wiki as, "dust bowls, dust storms, famine, habitat damage, malnutrition, mass migration". I don't see swarms of Londoners travelling to the Lake District yet.

"I don't see swarms of Londoners travelling to the Lake District yet."

They should do- it's a beautiful part of the country.

I echo the infrastructure point- we've had naff all rain for sure (WHATEVER the reason), but didn't i read somewhere that somewhere approaching 40% of all our water is 'lost' in the system due to leaks etc??

I think this may have been for one specific water company, but i'm sure problems like this will exist elsewhere.

97% capacity available in Yorkshire. Didn't they say that with man made global warming there would be a lot more rain! Also snow was another sign that global warming was happening.

At least in the SE of England, the last two years have seen below average rainfall, but neither have been unusually low, i.e. under 600mm, and at the end of 2011, the 10 year MA was almost exactly the same as the 1961-90 mean, and the 30 year MA was higher than the 1961-90 mean.
The lowest annual rainfall ever recorded was 396.4mm, in 1921 and the 10 year MA hit a record of 802mm in 2002. The 10 year and 30 year MA figures have recently been much higher than during the 19th century.
Seasonally, this winter and last autumn both had below average rainfall, although in both cases, the 10 and 30 year MA figures are both above 61-90. Last summer actually saw above average rainfall in the SE and while the 30 year MA is slightly below 61-90, the 10 year MA is above. The last three springs have had lower than average rainfall, with that in 2011 being the second lowest on record, after 1893. Prior to that, the 10 year and 30 year MA had been rising but have now fallen below the 61-90 mean. In fact, in relation to spring, the 61-90 period saw unusually high rainfall, compared to the 20th century mean, another example of the arbitrary nature of the 30 year period.
So any "drought" is probably a comination of lower than average rainfall last spring, autumn and winter. However none of these were unusual, compared to the historical record. Personally I think that the "drought" is more related to increased usage than to low rainfall.

#12. - Sheffield_city wrote:
"97% capacity available in Yorkshire. Didn't they say that with man made global warming there would be a lot more rain! Also snow was another sign that global warming was happening."
More snow or less?
As far as I can tell from the MO website, the major effect is going to be milder/wetter winters and drier summers, but that opinion seems to have changed recently. I can't find any definitive statement of whether overall precipitation is expected to be higher or lower.

Whilst it is a good idea to try to reduce water use this does have penalties. Germans use far less water than we do and German water companies are now spending up to 80% of income unblocking sewerage systems not flushed through properly.

I suppose it is quite difficult to define what a "drought" actually is - though at one time there used to be an official definition I believe.

Any prolonged rainless period (say a month) could be defined as drought - but obviously the affect would be dramatically different in hot summer weather from the same low rainfall in mid winter. Equally a very long period of below average rainfall could be given drought status - even if regular light showers kept everything looking green. We have the latter case now.

Low winter rainfall is particularly serious because once vegetation begins to grow, so much moisture is lost via transpiration, that only exceptionally heavy rain will make up the difference in summer. Growing vegetation intercepts most rainfall and there is almost no percolation into the ground, indeed soil moisture levels normally fall even in a damp summer. Presumably the current worry is that (barr exceptional deluges) whatever we have available now must last us until autumn.

I agree that massive changes in lifestyle/water use/population/urbanisation greatly exacerbate this problem and there seems little obvious link with climate change. However one "oddity" is that for much of the winter we have been under the influence of "westerly" circulation (normally wet). This year has produced a real wet west/rainshadow east contrast (due to the v. mobile circulation perhaps?).

Meteorological connundrum for anyone:

The last few days here have been very gloomy all day (total contrast with brilliant WE). However, just as sun starts setting, cloud begins to thin and by dusk, sky has been completely cloudless - if a bit murky.

So, what's the physics/meteorology for this?

Normally, sun would be expected to "burn off" low cloud of this sort (indeed this has been the forecast to some extent). Yet here we have the very reverse. It is not the first time I have noticed this phenomenon, but the last two days have been carbon copies. Of course, sun can cause thermal convection and cloud cover after a clear night but in this anticyclonic weather, this seems highly unlikely to be an influence - particularly as the cloud cover is present from dawn.

It's reassuring that times have not changed with the weather. Weather is after all 'weather'. I have been around a lllloooonnnnngggg time and feast and famine has always been the order of the day.

Difference I would guess these days is that we are so reliant on stability to survive with our population growth and global distribution networks that we notice it more.

Feels good to me. BTW. I live in California and we have been deluge the last few days. Sorry about the gloat!!

If a striker regularly scores 40 goals a season, then has 2 seasons where he scores 28 goals, would you say he is having a goal-drought?

A gent who "meets" 10 ladies a year, and then for 2 years he only "meets" 7 - is he having a dry spell?

I could continue..

This is not a drought. In fact it weakens the true meaning of the word so that when a true drought occurs, wolf has already been cried out.

1976 was around the time of a double dip la nina too. Just coincidence?

Did anyone see Watchdog on the 主播大秀 tonight? Seems the leaks are still happening.

I did a quick check of the latest figures and the water companies are losing about a quarter of the water supplied through leaks. They can't afford to fix the leaks because they only made around 拢1.5 billion profit.

OFWAT, the pretend regulator, has announced that average bills will increase by an inflation busting 5.7%. Water companies don't consider water to be a scarce resource; it's more of a cash cow.

" Water companies don't consider water to be a scarce resource"

Water isn't. But drinkable water in the right location can be.

QV, couple of points that maybe of interest, just in case you haven鈥檛 seen them:-

鈥淚n March 2012, we have supplemented the CRUTEM3 data with the new CRUTEM4 version (see Jones et al., 2012). The datasets have been developed in conjunction with Hadley Centre of the UK Met Office. These datasets will be updated at roughly monthly intervals into the future. Hemispheric and global averages as monthly and annual values are available as separate files.鈥�



Also on that page HadCRUT4 NH & SH numbers posted up to 2010. I have not checked the MO site yet.

Second point:-

鈥淥n the adjustments to the HadSST3 data set鈥�



The whole post needs reading and it is taking some time to digest, but the following is from the conclusions:-

鈥淭he principal effect of these adjustments is to selectively remove the majority of the long term variation from the earlier 2/3 of the data record and to disrupt circa 10-11y patterns clearly visible in the data. These changes are fundamentally altering the character of the original data.鈥�

Note: the post is by Greg Goodman and Dr Curry makes the following comment:- "The views expressed in this post are those of GG, and not my own."

Should be interesting to watch developments!

#23. greensand wrote:
鈥淎lso on that page HadCRUT4 NH & SH numbers posted up to 2010. I have not checked the MO site yet."
Thanks greensand, I was going to post on this, but you beat me to it!
I can't actually find the HadCRUT4 figures on that site, did you mean CRUTEM4?
The NH/SH data are available on the MO website too, but in a slighly more convoluted way and the global average figure, and some seasonal data, which is not on the CRU site.
I found out about the availability of CRUTEM4 data from an article on the GWPF website but I don't know how long they have been available.
I notice that the CRUTEM4 global figures don't include 1850, although that is possibly something to do with the fact that the Sept. 1850 was missing from the CRUTEM3 data.
Also, for some reason, the SH data from the MO website don't start until 1856, which is odd. I will be getting in touch with the MO about that.
I am also slightly puzzled by the calculation of the global figure using the formua (2NH+SH)/3, unlike CRUTEM3, which uses (NH+SH)/2. The explanation for this is as follows:
"Calculating the global mean as the land area weighted average of the northern and southern hemisphere averages helps prevent the value becoming dominated by the Northern hemisphere, where there is typically greater observational coverage. "
But surely, doubling the NH figure would have the opposite effect?
The explanation for using the formula (NH+SH)/2 for CRUTEM3 is :
"Calculating the global mean as the mean of the northern and southern hemisphere global averages helps prevent the value becoming dominated by the Northern hemisphere, where there are more observations. "
Surely they can't both be true?

Anyone watching the tropical cyclone Lua about to hit the top of Oz? Could be bad. Sea levels in that part of the Indian ocean are at their highest on record (partly due to sea level rise and partly due to the La Nina pattern):

100 mph winds are driving swollen ocean towards shore. Big storm surge seems inevitable. Due to hit tomorrow morning.

24. QuaesoVeritas wrote:

"I can't actually find the HadCRUT4 figures on that site, did you mean CRUTEM4?"

Not often your'e wrong QV and you are right again this time! Yes, I did mean CRUTEM4, sorry for any confusion. In a rush for an appointment (well that is my excuse!)

Re the calculation "(2NH+SH)/3, unlike CRUTEM3, which uses (NH+SH)/2" I am also puzzled and have no answers yet. Until the last few days I was under the impression that the "gridded products" filled in the whole globe so if there was no data in a grid, the value was "filled" by extrapolating from neighbouring grid cells.

I have now been told that this is not the case with HadCRUT3 & 4:-



This has left me pondering the effects this may have, especially in the light of "(2NH+SH)/3". Also see another comment on the same blog:-



I am still pondering!

#26. - greensand wrote:
"This has left me pondering the effects this may have, especially in the light of "(2NH+SH)/3".

I haven't read the comments yet, but as far as my calculations go, most of the recent increase in CRUTEM4 seems to be due to using the (2NH+SH)/3 method, rather than the (NH+SH)/2 method.
Up until about 1915, both methods produce much lower results than CRUTEM3.
It seems odd that having said they want to minimise the dominance of the NH, they then double the NH figures in the average! I can't see this doing anything other than exaggerating the NH warming trend.
I have sent a question on this, and the "missing" SH figures to the MO.
Meanwhile I have reverse calculated the SH figures, using the global and NH figures.

GS & QV

I suppose the release of HadCRUT4 will be accompanied by peer reviewed explanation?

to Lateintheday# 173 (previous blog)

Who wrote "1.What we know we know; 2. What we know we don't know; 3.What we don't know we don't know".........(!)

Hmm..... OK. So everyone faced with the AGW question has to deal equally with this.

One flaw in your argument is that placing "evidence" in each catagory is not just a matter of opinion - certainly not yours or mine.

A substantial majority of experts in the field consider that there is enough evidence to show that AGW is a fact. (cat.1). They have arrived at this conclusion not by opinion - but by the accepted scientific process - which though not perfect, nor rarely absolutely certain - is much the soundest way of finding the truth and eliminating error due to personal bias.

Presumably you have regard for this scientific process - because if not, it would be tantamount to saying that it is a set up or "conspiracy" - which you claim not to believe.

Any doubts or questions about the accepted evidence/hypothesis must also be put through the scientific process, before becoming admitted as "evidence" rather than speculation. Until that process occurs, such speculation, however convincing or well argued, must weigh but lightly.

So, for sceptics to claim there are "too many doubts" about AGW - is purely a non evidence based viewpoint - and remains so UNTIL scientifically validated. So - step up and put your doubts forward - not to the sceptic press, or to an unknowledgable public - but to scientific peers. As soon as those doubts are properly assimilated into the evidence, they will be taken into account (or equally,perhaps, rejected as groundless).

It's no use nursing yourself behind a somewhat unspecific haze of obfuscating "doubts" - pleasantly nourished by the unvalidated words of "sceptic scientists", allowing yourself to be deceived that the evidence for AGW is insubstantial and weaker than it really is.

@22, PingoSan wrote:

鈥� Water isn't. But drinkable water in the right location can be. 鈥�

I entirely agree but with the rainfall we have and the price we pay that should not apply to anywhere in England.

Hi jkiller . . . you start with
"One flaw in your argument is that placing "evidence" in each catagory is not just a matter of opinion - certainly not yours or mine."

Then whose? If not yours and mine then we simply accept what we are told. This is daft. It's the epitome of an appeal to authority.

then you continue . . ."a Substantial majority of experts . . ."
Oh dear - deja vu.

then you continue . . . "you have regard for this scientific process"
From what I have read, the scientific process has been redefined by climate scientists.

then you continue . . . "Any doubts or questions about the accepted evidence/hypothesis must also be put through the scientific process, before becoming admitted as "evidence"
errr . . . no, I don't think so. The 'doubts' are an intrinsic part of existing, well defined logic, which is essentially how we define the quality of evidence. We accept evidence because there is little room for doubt.

then you continue . . . "So, for sceptics to claim there are "too many doubts" about AGW - is purely a non evidence based viewpoint"
You are saying that sceptics should accept AGW despite the lack of evidence. That any scientific proposition is de facto sound, until the doubts have been peer reviewed.

and finally "allowing yourself to be deceived"
If I am deceived by the 'unvalidated words of sceptic scientists' then why do you assume I am complicit in this?

My view is that climate science relies to large extent on circumstantial evidence. How this is weighed is very much, a matter of opinion.

Well, it looks like the small fall in AQUA CH5 and other channels around the 11th was a false alarm, as the temperature of all channels has continued to increase since then.
The daily anomaly has exceeded the average figure for the first time since January 3rd., which suggests that UAH is currently around 0.15c, although the cumulative temp. for March still probably puts UAH around zero.
It's anybody's guess where the figure will be by the end of the month!

32. QuaesoVeritas wrote:

"It's anybody's guess where the figure will be by the end of the month!"

Isn鈥檛 that always the fun with this planet? Some say they can predict it, some even say they can control it!

The short term is of interest, provides insights and may eventually lead to understanding, but at present it is just interesting to watch.

A spike in Reynolds SSTs and Maun鈥檚 predictive 鈥淓xtended Range NCEP GFS Temperature Anomalies鈥� analysis suggested a return to average over the last days and maybe a few more to come.

Of late Reynolds SSTs declined to be below the level at this time last year:-



Maun shows positive anomalies for the next few days, turning negative about the 24th. Nobody knows for sure but we will watch.



Have fun!

NCDC/NOAA anomalies for February as follows:

Global = 0.3653c, compared to a revised 0.3637c last month (previously 0.3871c)
N.H. = 0.3206c, compared to a revised 0.3757c last month (previously 0.3984c)
S.H. = 0.4171c, compared to a revised 0.3589c last month (previously 0.3827c)

After adjustment to 1961-90, the February figures are equivalent to 0.2273c, 0.2309c and 0.2413c respectively.

So, the global anomaly is almost identical to last month's revised figure, but slightly lower than the original figure, while N.H. is down and S.H. up.

Based on this, and the February GISS anomalies, I expect very little change in the global HadCRUT3 anomaly, and a slight fall in N.H. and a rise in the S.H. anomalies.

Unfortunately the February HadSST2 anomalies have not yet been published.

To Lateintheday #31

An appeal to authority - yes of course! - "authority" meaning "someone who knows a lot about it". This is the normal process by which we understand most complex things, surely.

If you rely heavily on your own opinion - then your earlier "what we know/ don't know" etc argument needs to be applied even more rigorously - since the chances are YOU know a great deal less than you think. We don't "simply accept what we are being told". But if we have questions or doubts, we can't hide behind them indefinitely as a means of obfuscating the truth.

I wonder where you have picked up the bizarre notion that climate science has re defined the scientific process? Is it even worth me asking - how much objective credibility does this opinion itself have? If true, is it really likely that climate scientists would have the regard of such as The Royal Soc. etc. I mean - do yourself a favour for pity's sake ( and don't say the RS has suspended scientific principles as a special case!).

There is nothing wrong with doubt and scepticism - obviously doubts are "an intrinsic part of how we define the quality of evidence". But- AT SOME POINT-they have to be validated AGAINST the evidence. You might have doubts that an areoplane won't fly - but the only way to find out is to test it, not just sit there refusing to believe that planes will ever fly because of doubt. Surely this is obvious.

And YES, sceptics should accept the evidence for AGW - WHEN it is derived by the scientific process. Argue and participate - but don't just come up with endless evasions. (Hence, I suppose, all this stuff about climate science not conforming to normal standards - a conspiracy in effect). So what is your alternative to deciding the credibility of AGW? A vote in parliament; a Gallup poll; a decree by the Archbishop of Canterbury?

Oh, but of course - I've missed the obvious one - YOUR opinion! Well, I have to say, that if I had to choose between my personal assessment of a scientific problem like AGW or that of "the majority of climate scientists" (incidentally, where is your OBJECTIVE evidence that this statement is untrue?) - I wouldn't have the sheer crass hubris to assume I knew best! You, and many other sceptics appear to think otherwise.

I wonder -can this really be what's at the bottom of it all? EGO!

Hi jkiller . . .
Part of the problem is that the AGW plane isn't flying very well. It's been losing altitude for around 10-15 years and they appear to keep lowering the ground just to keep it in the air!
Ego? Well my opinion means nothing - just ask my wife and kids! Still, it's as valid (or not) as the next layman's. Now if I were simply one of a number of non-expert sceptics who disagreed with the scientific consensus on AGW, I'd be on very slippery ground indeed. But among the "many other sceptics", there are scientists, engineers, meteorologists, solar physicists etc. etc. Fewer in number to be sure, but nevertheless, many highly educated professionals who ARE qualified to offer an informed opinion - if only on the specific aspects of climate science that they are familiar with. Hence the importance of the detail - not simply the big picture. So despite being on the contrarian side, there is a sound and rational basis for my scepticism - you're just going to have to live with that.
You seem to have experienced some sort of AGW epiphany - ex sceptic who now sees the light. If you'd care to put your strongest evidence forward in support of AGW, perhaps you can convert me step by step!

IT'S ONLY CYCLICAL-REMEMBER THE FLOODS 2007?

#37. - l i dawson wrote:
"IT'S ONLY CYCLICAL-REMEMBER THE FLOODS 2007?"
I agree that UK rainfall patterns are essentially cyclical, or at least random, and are not related to "climate change".
However, supporters of "climate change" would argue that such events are "more likely" with "climate change", and are therefore "proof" that "climate change" is happening.
There was even a report by the Centre for Ecology and Hydrology, which concluded that the 2007 floods were a "singular episode" and not linked to "climate change".

However that didn't prevent some proponents of "climate change" using them as the sort of thing which are more likely to happen with "climate change".

The hypocrasy of statements such as the following, is not hard to see:

"No one can yet attribute the flood events of the past week, or indeed, those of June, when Yorkshire suffered what Gloucestershire and Worcestershire are suffering now - again from one single day's rainfall - directly to global warming. All climates have a natural variability which includes exceptional occurrences.

But the catastrophic "extreme rainfall events" of the summer of 2007, on 24 June and 20 July, are entirely consistent with repeated predictions of what climate change will bring."

I am sure that what is true of the UK floods is also true of world wide extreme weather events, with some having already decided that "climate change" is happening:


The default position of supporters of "climate change" is that every unusual weather event is caused by "climate change", unless proven otherwise.
The default of sceptics (including myself), is that every unusual weather event is caused by natural variability, unless proven otherwise.

Sounds odd but there's a lot more to flooding than precipitation. Obviously it starts with precipitation, but in the UK at any rate, land management practices are often what turn a drama into a crisis.

We tend to plant free-draining coniferous forests on high ground and allow livestock to degrade hillside vegetation and trample the ground hard. When the rain falls on the hills, where most of it does, there is less vegetation or soil to absorb it than would naturally be the case. More water simply makes it from the hills to the river systems than it used to - even without increased precipitation from climate change.

Then we pour good money after bad into building and maintaining flood defences to protect housing we built on the river's natural flood plains. Now, with all this extra water flowing off the hills, the river no longer has even the natural spaces it used to, when flow was lower on average, to spread out and relieve its burden.

So we have i) (probably) increased the likelihood of extreme summer rainfall events, ii) reduced the hillside's capacity to contain rainfall by stripping away its natural vegetation and soils and iii) removed the river's 'pressure release valves', i.e. its natural flood plains, by building houses on them and blocking them off with walls.

We are now spending a fortune curing the 'symptoms' by building ever more expensive and futile flood defences, while ignoring the underlying causes of the flooding.

The future results are fairly predictable, are they not? Villages downstream of all this increased flow are going to suffer increased floods, erosion and degradation, and areas adjacent to the river that never flooded before are going to find themselves as future floodplains.

#39. - newdwr54 wrote:
"Sounds odd but there's a lot more to flooding than precipitation."
I don't think it sounds odd at all, I agree with everything you say.
Ever increasing urbanisation is destroying the natural drainage of land, which puts more rain water into the drains and rivers than was ever the case.
However, this is rarely mentioned when flooding is discussed in the media.
It is difficult to say whether heavy rain events are "normal" or not, but I suspect that they have been as common in the past as they have been recently, but urbanisation has made them more likely to cause floods.

40. QuaesoVeritas:

Nice that we agree on something again!

Changes in rainfall patterns should be measured by rain gauge records, not increased incidences of flooding.

Lateintheday#36

"Epiphany" - not really. I have merely defered to the PROBABILITY that people who know far more about this subject than I do and who are convinced that AGW is almost certainly true, are correct. I am quite prepared to change my position again if the balance of probability alters. This sounds dangerously like "he who believes in nothing will believe anything".

However, my actual immovable position rests on the basis that the scientific process is the best means we have of determining the truth. Although not perfect and rarely certain, as well as being subject to perpetual revision, if we don't have respect for this process - what methods do we use instead? The imperfections and possible errors of scientific consensus are in my view far outweighed by the dangers of accepting more maveric views of the truth - even if - on odd occasions, these maveric views turn out to be correct in the end. But contradictory views must prove themselves against the established one and stand or fall on this basis. Attempts to infer that if sceptic views cannot prevail - then somehow the rules themselves have been fixed in favour of AGW are not only silly, but in the end are downright dangerous leading to a slippery slope of manipulation and error.

The "climate consensus", for all its possible weaknesses has been arrived at by rigorous scientific process. It may well be that the views of your sceptic experts have merit. But it would seem that they have been insufficient to tip the balance of probability away from AGW in the eyes of those who understand this subject best. But who knows, this may not always be so.

I don't know if this will "convert" you or not. I too am a "layman" so don't expect me to give you detailed statistics about climate and AGW - because, I readily admit, I do not have the knowledge.

Regards JKILLER

#28. - newdwr54 wrote:
"I suppose the release of HadCRUT4 will be accompanied by peer reviewed explanation?"
There is a paper on the on the MO website but I haven't had time to read it fully yet.
Having had more time to think about this, what I think the MO mean by "preventing the value becoming dominated by the N.H., is the use of this method of calculating the average, rather than averaging all of the individual stations in the N.H. and S.H.
What I think is interesting however, is that they have changed their mind on the best method of doing this between CRUTEM3 and CRUTEM4, which may give the impression that they are "fiddling" the figures. If the new formula is more "correct", then they have actually been understating the global land temperature in CRUTEM3.
The (2NH+SH)/3 formula is probably a more accurate method of calculating the global land temperature average than (NH+SH)/2 but it does give more weight to the NH.
Also, having applied this logic to the land temperature figures, in the form of CRUTEM4, will they also apply it to the sea temperature figures, since there is more sea in the S.H. I think that the ratio of S.H. sea to N.H. sea is about 1.3:1, so the formula would have to be something like (NH+1.3SH)/2.3, although I am not sure.
At the moment, the MO uses the formula (NH+SH)/2 to calculate the global HadSST2 average, but there are apparently more observations in the N.H., despite the fact that there is relatively less sea.

I have noticed that there is now a link on the MO website to HadCRUT4, although it doesn't seem to be possible yet to download the actual data.