HighPressure
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Posts posted by HighPressure
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In North West Kent we have just measured our hghest rainfall rate to date :
195.2mm / 20:29
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I wonder if the aurora is related to Sun Dogs? My son took these images today in South London :
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1 hour ago, HighPressure said:
Took this a few mins ago, Downs NW Kent :
Latest pic, still snowing :
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Took this a few mins ago, Downs NW Kent :
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Snowing quite haevy here on the downs, it seems to be turning back into snow along the M25 Surrey / Kent
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4 hours ago, richie3846 said:
I've been researching into the drought of 1976, to see how it compares to this year. People have gone on the record and said it's not as serious as 1976, because we have much better reservoir levels, and the first part of 76 was much drier than this year.
These are valid points, but I'd like to draw attention to two things. Firstly, this graphic is the maximum soil moisture deficit for the peak of the drought. Soil moisture deficits in the south this year, at the end of July, we not far off these extreme figures of 76. The number of places that missed the majority of August's showers this year, may have deficits approaching or even exceeding 76, right now. With little rain in the forecast, it's likely that places in the south will have deficits of 150mm like 1976.
Secondly, the 76 drought ended in a flash. It was all over by October, thanks to a wet autumn. What has changed in the UK since then, is that autumn in some years, many years, have now become summer extensions. Whilst there is a reasonable chance of a wet autumn of course, statistically speaking, there is a greater chance than 76 of a less wet autumn, as we all know how many September to October periods of recent times have been quite dry (a couple have been very wet too). I'm not making this up either, the met office recently went on record to discuss September becoming an extension of summer, in a podcast.
Given the higher temperatures, longer growing season, and higher risk of a settled autumn, this current very severe drought has the potential to extend into next year if we have rainfall October to March below average, even just a little below average. Even in average rainfall from September onwards, there will be some delay to the groundwater recharge season, because it'll take longer than usual to replenish the 150mm dry soils, which is a good 40 to 50mm drier than average, which for some is almost a month of average rain.
So fingers crossed for some decent rainfall this winter, as without it, things could become very difficult next year. Even with average rain, groundwater could still be below average until the following winter in some areas.
People often say that these things have a tendency to balance out, which they have done at times in the past, but with an uncertain climate, I don't think we can rely on that so much these days, living in hope that we'll have heavy rain after a period of drought.
On a personal note, if it does lash it down all winter, it'll be bittersweet for me, as I work outside a lot of the time, and I can't say it's much fun, even if we do need it, I'll still be hacked off if it rains every day for weeks
I think the problem with comparing 1976 to this year is that we know how 1976 ended, the rains came. We simply don't have a crystal ball to see how this autumn and winter will play out.
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38 minutes ago, *Stormforce~beka* said:
What is a minister of drought meant to do? Make it rain?
I seem to remember they bought in a genuine Indian Witch Doctor to do a 'Rain Dance' in 1976, don't think it worked but maybe worth another shot this time ?
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7 hours ago, Nick L said:
A resource as precious as drinking water should never have been left in the hands of the private sector.
Hi Nick, here is an exert from the email I sent my MP yesterday, I worked for 20yrs in the water industry (5yrs for SES and 15yrs for Thames) from the late 80s to the late noughties. I worked throughout the privatisation period, and was part of many changes and improvements made
"My experience is that the industry has been wholly dishonest since @1995 when all obvious savings were exhausted. The industry plays cat and mouse with the regulator, choosing to pay fines because it is cheaper than providing long term solutions. Risk assessments are carried out on 1 in 5 or 1 in 10yr drought events, so the companies know that they need to plan for these, but they don't. Maintenance procedures and standby capacity has been consistently reduced for cost saving purposes. Companies such as Thames Water report their own figures such as leakage to OFWAT and they are routinely misrepresented. This manipulation was so bad at Thames that we needed to create an entirely different system for calculating London's demand as the official system was rigged to the extent it did not represent the true numbers.
In truth some of the smaller companies such as SES Water are a lot more honest as these were never part of the privatization process as they have always been private companies."
You may also be interested to know that there has always been private water companies in the UK, here is a list of them:
Affinity Water
Bournemouth Water
Bristol Water
Cambridge Water Company
Cholderton and District Water Company
Essex and Suffolk Water
Hartlepool Water
Portsmouth Water
SES Water
South East Water
South Staffordshire Water-
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7 hours ago, SnowBear said:
To be fair many water main burst during hot weather are caused by ground heave, especially in clay areas. You can try and prevent, but you won't prevent all of them.
This one in London may be the result of a number of reasons, perhaps older pipes, drying clay under London itself, plus working and reworking of roads and paths by cable companies, gas, electric and so on.
The main that burst was probably the one we knew as the East London 36inch, it is a very old main and has burst many times.
The biggest clue is the time it went @7am just before demand really gets going the time of day when pressures in the network are around their highest. Due to what I suspect is and has been high demand the overnight window for refilling reservoirs is just a few hours, which means you have to take the pressures to their limits, and accept the associated risks.
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Anyway got plenty of stuff still growing in my Kent garden :
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A couple of things to note today, SES water don't plan to introduce a hose pipe ban, which is interesting that they rely primarily on ground water via boreholes and wells, it seems to suggest that groundwater levels must be reasonable.
The other thing I have leant today is that the great Thames Water desalination plant at Beckon opened just after I left, is not in operation and will not be used in the event of a drought order. This is because it doesn't actually work properly, engineers forgot to factor in that salt levels rise and fall during the day making the plant completely unreliable, and unable to yield anywhere near the 150Mld promised. I can only continue to hope that companies like Thames are exposed for the shambolic way they run our water supplies.
Money is that matters to them!
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13 hours ago, mountain shadow said:
The difference is, the Chinese are loaded, the UK is massively in debt.
That said, surely it can't be that expensive to pump water from the North to the South? Provided, the North are suitably compensated.
The point being is that our island is not short of water and engineering wise the solutions are quite simple. Given that 10s of billions of pounds has been taken in profits since privatisation, I do not think it unreasonable that these companies should be made to put supplying their product at the top of their list.
During my time in the water industry, I even discussed the plausibility of powdered water, I kid you not, dry water in the form of powder exists
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13 hours ago, Nick L said:
The cost involved I suspect and the private water companies aren't so keen on splashing out (excuse the pun!). Pretty sure the likes of Fuerteventura get all their water from desalination plants, however.
It's an energy-intensive process but as an island that has ample potential for renewable energy I think it's something that has to be considered, especially considering climate change and population growth. As ever in this country though, short-termism trumps long term thinking.
Couple of things, there is at least one desalination plant in the UK, Thames Water were building one at Beckon on the north bank of the Thames when I left. It using a desalination technique known about since the 1st book on water treatment called Reverse Osmosis. I understand the plant cost @£250m and can produce @140-150Mld, and it cost about double that of standard water treatment, but a lot cheaper than other methods.
The Chinese have a huge transfer scheme underway, it just shows what can be down if the will is there :
The South-North Water Transfer Project in China - Internet Geography
WWW.INTERNETGEOGRAPHY.NETThe South-North Water Transfer Project in China. Find out about the main features of the project along wit its advantages and disadvantages.-
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11 hours ago, kold weather said:
Thats more what I'm looking for, frontal rain, persistent but not too intense for reasons you say. It did look for a brief time like we were going to get some of that, probably no where near enough but every little helps when its not too intense.
Still some possiblity for Monday/Tuesday of some rains, but beyond that signs of high pressure moving in seem to be increasing again.
At the risk of boring everyone, September / October are key months, if they are dry, not only do the reservoirs keep dropping but they become difficult to refill.
One thing they found out in 1976 (well before my time), is that you cannot just refill a clay core reservoir as fast as you like. Clay as you know dries out and we see those famous cracked ground photos as in this thread. If you refill too quickly the clay does not have time to gain moisture, so the water comes out the cracks and runs down the outside of the banks, and can undermine structural integrity.
Each reservoir has a maximum daily refill rate which we used to calculate each morning before setting the abstraction regime, its only cm's per day. If you start low you have a risk of going into the following summer without maximum storage, and the cycle repeats...
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8 hours ago, kold weather said:
Whats really becoming more worrying is we've got several LP systems that are set to move through in the nearby area and despite that there really isn't much rain forecasted on the fronts at all. A possible 5-10mm isn't really going to make up for the dryness seen in the last few months in particular.
This next week is vital because if we can't get a decent frontal rainfall (I mean a 20-30mm jobbie over a 3-4 day period, at least) then we appear highly likely to move back into a very dry pattern and we would probably be looking for thundery rain from the south after a hot snap to break the pattern down.
The only upshot is time is starting to swing back in our favour, as the days start to quite rapidly reduce in length through August which reduces the time temperatures are at/near their peak vs June/July.
Still a warm and dry August probably will put the SE at least clearly into official drought territory.
Unless we get steady and persistent rain in August, any rain is likely to have no real direct influence on the water supply situation.
Factors that do have an impact, last week of July and first couple of August see reduced demand in urban areas up to 10% in London as so many people are away and businesses are closed. Cloud and cooler temperatures will also help reduce demand, people do not water their gardens if it looks like its going to rain.
A deluge of rain is often counterproductive especially after a prolonged dry spell. The ground is hard so any rain which does not evaporate becomes runoff into the rivers, that will wash all those gathered pollutants and organic materials straight into the river. That causes oxygen depletion, kills the fish and can actually stop any abstraction hat was running.
They end up having to get this chap out :
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18 hours ago, richie3846 said:
Wow that is a fascinating insight, I had no idea about all that. It's scandalous really, because from what you say, Thames Water aren't doing enough to protect the ecology of the river when it comes to a dry year like this one. Is this the same for Farmoor, with the reservoir needing to be full to work well? It rarely runs low, but this year the flows at Farmoor are practically grinding to a halt, so I can't imagine Thames Water can abstract any more water without a drought order.
Although I have been to Farmoor, and it is a Thames Water reservoir, the part of the Thames Valley controlled by Thames water in the Oxfordshire region is not connected to the London region so I don't have much personal experience of running that system. What I can say is that Farmoor is of similar construction to those near Heathrow and is filled from Thames abstraction again in a similar fashion. I can't speak for the hydraulics of the system itself.
My experience comes initially from a tiny water company called Sutton & District Water which was all boreholes/wells and is now part of Surrey Water. The majority of my experience comes from being a senior controller for London's water supply for 15yrs. I have seen most things
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On 23/07/2022 at 19:11, richie3846 said:
In addition to a summer drought, it's also a longer term drought affecting groundwater levels, therefore river flows in much of the south. It's a complex balance, that requires decent winter rain and saturated soils, in order to recharge the groundwater which gives base flows for many rivers.
One of the problems of a dry summer is it can delay the groundwater recharge in the winter, as it takes longer to wet the soils up in the autumn.
Even though 2018 was even drier in the summer, there was no chance of water restrictions in the south because of high groundwater after the beast from east. This year is different, because the winter was lacking in recharge, and this is why rivers such as the Thames are running at very low flows. If August was hot, we can expect water restrictions to help preserve the base flow of the rivers.
As someone that was heavily involved in London's water supply for 2 decades (1990s-2000s) I have seen several drought or near drought situations. The first thing to say is that plenty of water flows down the Thames each winter to refill London's surface reservoirs to the maximum. The Thames supplies @70% of London's water, the Lea Valley @20% and the Kent Boreholes @10%.
Thames Water are saying they supply 2100-2400 Mld (millions of ltrs per day), that is actually a reduction on the peak demands of the 1990's where I saw up to 2800 Mld, summer 1995 was one year I can remember. The boreholes in Kent produced @200-250Mld, so a very small amount in comparison.
So why do we face possible drought restrictions now? The surface reservoirs were fall again this spring, containing @220,000 Million Ltrs, which in theory should equate to @100 days of London's supply needs without the need to abstract more from the River Lea or Thames. The problem is the system does not actually work, so despite the theory, there actually isn't 100 days supply, in fact no where near that. In reality 30 days is probably stretching it, before they are crying out to abstract, and during the summer that is not easy when you have 450Mld pumps and one of those can quite literately suck the Thames dry (It can't because it will conk out on low suction before that).
Because most years it is possible to keep some abstraction going from the Thames and the Lea, the real situation isn't actually seen because the reservoirs can be kept above about 70%. Once the reservoirs dip below 70% you get problems, firstly with water quality, the more shallow the water is the more issues you get with algae, that causes blinding of primary filter beds which mean they need backwashing more often, and that reduces output from works. The next issue you find is that the system is gravity fed, so as you lose head you lose input rates, there are pumps but they cannot cope with anything close to even average demand.
In short if London suffers water restrictions this summer, it will be entirely self inflicted, due to lack of infrastructure improvements and investment over many years. Despite the many risk assessments that have been stuffed under their doors or left on desks, Thames like many other water companies put the pursuit of profit first and only make minimum infrastructure changes when they get caught with their pants down.
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11 hours ago, Ed Stone said:
Also, I've noticed many of them (not all, I hasten to add!) adhere to some pretty peculiar political mores; in particular toward extremes of either left- or right-wing tenets. So, maybe the ability to ignore objective reasoning/research and favour rigidly held dogmas (be those dogmas political, religious or both) is, at least in part, psychological?
I would be one of those I guess
Seriously isn't those who challenge mainstream thinking that tend to make the discoveries, especially in science. The likes of Copernicus and Columbus. would have been considered completely mad if forum such as this existed back in their day.
Science is to be challenged, if only to be proved wrong.
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9 hours ago, SnowBear said:
I think it's far more complex than that. If we look at the seasons, once Midsummer's day passes we don't see a gradual cool down from then to the Winter Solstice, infact the warmest part of the year is after Midsummer's day as we have just seen, July and early August often being the hottest part of the year once the heat has built up.
So although the Milankovitch cycles may mean less radiation is reaching the surface right now, there are forcings from before, perhaps hundreds of years back, still to play out before we start to cool.
I don't deny we have meddled in our earth's climate, but I don't think it's all down to us, or CO2.
One big question still to be answered in the Milankovitch cycles is why it changed about 800k years ago from a fairly regular 41k year cycle of ice ages into a new cycle.
The Mayans fairly accurately gauged precession, that cycle ended in around 2012 with the restart of their calendar, but it will be some time yet before we feel the effects of that change.
So what exactly is going on? In my view mini deserts and heat pumps in every city getting larger yearly, the wasting of forests, changing land usage (look at just the UK, once covered in forest, now fields and buildings etc), wasteful and unnecessary journies and a whole host of other small changes being made to the earth all making a big difference.
Its quite right we should all reduce our carbon footprint, we know its causing warming and not good, but there are so many other feedbacks and behaviours we need to look at too.
I fear they won't be, far too much money is being made from it.
But not all of this is down to us, the climate constantly changes, and always has done, sometimes quite rapidly. In geological terms we have been on this planet a mere blink of an eye.
So many parameters in a chaotic system.
What we need to do is work out how to adapt and stop behaviours which exasperate climate change, and that's beyond just CO2.
Less air travel, less unnecessary journeys, less material greed for things we don't need, more greenery, and generally more respect for the planet we live on.
The main gist of my post is that the use of fossil fuels and production of Co2, needs to radically be reduced before we argue the details of climate change.
The fact that fossil fuels are not limitless and the associated geopolitical issues, mean they really have to be phased out. Everything that lives and breaths on earth has an impact upon it to some extent. Man has the ability to destroy itself of that I have no doubt, but I do not believe we can have a permanent impact, as we would be long gone before that could happen.
Oceans are the biggest driver of climate, their take up of Co2 plays a major part of the process. In fact the 1st ever post I made on netweather was about the Ozone layer and 'possible' impacts on climate change and extreme weather events, that was back in 2005. I believe the climate is changing, it is warming, but I have never really been confident with the idea that it was simply down to mans Co2 output. It also intrigues me that the time line for Ozone depletion fits pretty well with the advent of increased extreme weather events?
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9 hours ago, Ed Stone said:
I've never said that the elements you mention don't affect the atmosphere, or that they don't need investigating -- of course they do!
But, not only do we know enough about CO2 to be quite certain of the atmospheric roles it plays, we also have the technologies already in place that would enable us to use renewable energy to power carbon-capture. So, we may as well get on with it!
Then again, there may well come a time (always assuming humankind hasn't nuked itself out of existence by then) when things over which we have no control -- Milankovitch cycles, plate tectonics, solar cycles? -- may decide it's time for us all freeze to death. So, what'll we do then?
One thing we could do, if only to buy ourselves time, would be to release all that sequestered CO2 back into the atmosphere. In effect, carry on doing what the biosphere has been doing since the time of the Great Oxidation Event?
My own view is that global warming is without doubt happening, our over reliance on fossil fuels isn't good, and we will run out of the stuff in any case. So commonsense says we should look to replace fossil fuels with renewables, as there are so many benefits before we even get to the climate debate.
As for the climate itself, its going through a natural warming phase, history does tell us that the climate changes, its likely that 1000 years ago the UK was warmer than it is now. Are humans impacting the climate? Probably a tiny bit IMO. Can humans cause long term or irreparable damage to the climate? No chance, mother nature cares not for humans, so she won't be too bothered if we do ourselves in, but she will simply cleanse the earth of any damage if any that we do.
A decade ago you could not give nuclear power away, now people are falling over themselves to build these plants, one today got the go ahead in Suffolk?
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On 18/07/2022 at 21:21, TN9 said:
Yea I agree ,profits before anything else ,I guess if there is any dodgy goings on some one will leak it
anyway on a serious note its all under the bridge now
When it comes to water under the bridge, I put a few gallons under once, you could say I gave the go for throttle up :
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This was the scene from Dartford Bridge this afternoon, there were more fires then shown here :
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Its breezy cool and raining here in NW Kent, I have missed something
Winter 2023/24 Chat and Discussion
in Spring Weather Discussion
Posted
Its currently snowing over the Pennines if that helps