Trees and CO2 capture - fun with numbers

Here are my workings, if you spot any glaring errors, please leave a comment. It's all round figures, I'm not going to bicker about anything more accurate than the first significan figure.

How many trees would we need to clear the backlog?

CO2 in atmosphere = 3,000 billion tonnes (3 x 10^12)
One-third of that is the increase since 1850 = 1,000 billion tonnes, this is apparently the Bad and Planet Warming portion. 1850 level is accepted as beneficial.
World population = 8 billion
Bad CO2 per person = 125 tonnes.
Trees consist of mainly CO2 by mass, plus a bit of H.
My mistake 1 - see comments - about half of the weight of a live tree is water.
An 80 foot tall hardwood tree = 9 tonnes
Let's say an average medium sized tree = 5 tonnes.
(A four foot long section of tree trunk with diameter 2 foot = 1 tonne, so if the main trunk is 16 feet high (two storeys of a house) plus 25% for boughs and branches, that's 5 tonnes)
So we'd need to grow another 25 trees per person to catch up. Sure, those trees will take decades to grow, but you have to start somewhere.

Ongoing emissions

At present, total CO2 in atmosphere is going up by 1% a year.
My mistake 2 - see comments - probably closer to 0.5%
1% x 3,000 billion tonnes = 30 billion tonnes.
30 billion ÷ 8 billion people = 4 tonnes per person.
Let's say each tree soaks up 0.1 tonnes of CO2 per year while it's growing (from above - 5 tonnes divided by 50 years)
That's 40 trees per person i.e. each person plants that many to offset the element of their lifetime emissions which aren't being soaked up naturally. This sort of overlaps with the 25 from above for older people, but hey.
The maths gets super tricky after that. People are born and they die. Older trees would have to be cut down once they reach maturity and are soaking up little additional CO2, then stored somewhere dry - to be replaced by new trees that are soaking up carbon as they grow. So I won't bother looking that far ahead.

Land area needed

25 to clear the backlog, plus 40 for ongoing = 65 per person. Number of trees in the world = about 400 per person
So broadly speaking, an increase in tree cover of one-sixth Forests (and presumably other wooded areas) = 31% of global land area
So that would have to go up to 36%, which seems do-able.

Applied to the UK

Decent sized trees per acre = 200. (In the dense wood at the top of my road, there are fairly big trees whose trunks were about 5 or 6 yards apart, so each tree has its own circle = 24 sq yards. 4,840 sq yards ÷ 24 sq yards = 200)
So the UK would need to 65 trees per person/200 trees per acre x 70 million people = 23 million acres, or 40% of the UK land area.
There's not that much suitable land (Scottish grouse moors, marginal farmland and such like) in the UK, but maybe we could get half-way there?
Countries like the UK that don't have enough land area per person and especially city-states like Monaco or Hong Kong will have to buy up some land in Canada or Siberia, where the land costs pennies, and let their trees grow there.

Alternative calculations welcome!

UPDATEs:

1. The two mistakes seem to largely cancel out. Trees only soak up half as much CO2 per tree as I thought, but we only need to soak up half as much CO2 = overall 90 not 65.

2. The Welsh government reckons that they need about 30 trees per person to be 'carbon neutral'. I assume (rightly or wrongly) that this is just to deal with ongoing CO2 increases and not clear the backlog, so ballpark, our figures are in agreement.

What's your optimum distance from a tree?

It would be easy to write a few paragraphs listing all the plus points of trees: they clean up the air; are net oxygen releasers; somewhere for birds to nest; provide welcome shade in summer; somewhere to shelter in a sudden summer downpour etc etc. So much so that politicians love being associated with tree planting (that was rather serendipitous - I noticed that post just as I started writing this one).

Most relevant for this discussion is that they look nice (whether that is an aesthetic thing or simply because they are associated with all the Good Things listed in the bog standard opening paragraphs on trees).

From closer up and on a practical point of view, trees are a pain in the arse. They undermine foundations; soak up so much water that other plants won't grow around them; drop leaves on your lawn and in your gutters; you need to prune the overhanging branches and go and grovel to your neighbours if a storm snaps off branches into their gardens (happened to me after the Great Storm of 1987 - in south Germany - it wasn't just a UK thing); a car parked under a tree gets covered in sap, seeds, leaves and bird poo (depending on time of year).

So there must be a trade off. Trees, yes, but Not In My Back Yard - which boils down to the question posed in the title.

For example: the back gardens on my street and the one behind it are stupid long (by London standards). The neighbours behind us had two large trees in their back garden,they looked great swaying in the breeze but were far enough away not to cause any inconvenience to Yours Truly (they didn't block any sunlight to our house or shed leaves in our garden). The neighbours extended their house a couple of years ago and they chopped down the larger one, reducing the quality of the view from our back garden (I still miss the larger one).

To my mind, that's the best place for trees - in somebody else's garden, at least twenty yards from your house, or at least twenty yards up or down the road from where you park your car.

But what if everybody thought like that? We'd have no trees on urban streets and gardens at all.

Hmm...

Yup. Definitely Global Warming.

This year's leaves haven't even finished falling off our apricot tree yet and next year's leaves are already starting to grow:

"Cornish cow gets head stuck in a tree"

Spotted by Thomas Hall in The Plymouth Herald:

The young bullock was found tightly wedged by a visitor at National Trust property Trelissick House.

Staff at the property in Truro, Cornwall, were quickly alerted and it took two hours of removing branches and chiselling away at the tree for the bullock to finally be freed...

"We don't know why he put his head in there, but another cow has been back to the same spot so there must be some nutrient in there that they like. The second cow also got stuck but was freed easily as we had already widened the hole the first time around."

"Houses built to last a century face being demolished after just 13 years to make way for a new forest"

From The Daily Mail:

A housing estate built at the start of the millennium in the hope it will last 100 years face being demolished after just 13 years due to a new re-forestation plan.

Wessex Investors built 100 traditional English houses in 2000 to provide homes for people who live and work in the ancient Cornish market town. But now the estate, which lines Millennium Avenue could be torn down to make way for forestry.

The plans which have riled many locals, are currently under examination by Cornwall council. Timber conglomerate Launceston Lumber plc, which intends to plant hundreds of slow-growing oak trees to produce high-quality timber in the Pennygillam area of Launceston later this century, insists there is no other option and their plan would provide 4 new jobs to local people.

"This has been on the drawing board for nearly two years and we are trying to accommodate everyone the best we can," managing director Andrew Pegg told The Independent. "'While several dozen families will be made homeless under current plans, we intend to install a couple of mobile homes in the new development to provide living accommodation for the forestry workers."

Fun Online Polls: Threats to trees & Mazda MX5 drivers

Thank you everybody who took part in last week's Fun Online Poll, results as follows:

What is the biggest threat facing the UK's trees?

Don't worry about it, they'll be fine - 53%
Horse chestnut bleeding canker - 21%
Acute oak decline (AOD) - 9%
Great spruce bark beetle - 3%
Phytophthora ramorum - 1%
Chalara dieback of ash - 1%
Other, please specify - 10%

Suggestions for "Other" included "Home-Owner-Ism", which I think is a bit far fetched, even by my standards, and Walter The Softie had this to say: "All of the above and together they will change the face of our streets, woodlands and forestry. Forever. They won't be fine but I'm not sure there's anything we can do about it, other than start liking sycamore."

So now we know.
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Her Indoors announced a while ago that she'd like us to buy a Mazda MX5 (preferably automatic as she doesn't have a proper driving licence, which seems like a bit of a contradiction in terms to me, a sports car with automatic transmission).

So I started paying more attention to them, and what strikes me is that Mazda MX5 seems to tbe sports car of choice for older people (i.e. I've not seen an MX5 driver yet who is younger than I am), so they are presumably for those people who chicken out of spending their life savings on a Harley Davidson when they have their mid-life crisis and who go for an affordable, practical little sports car instead.

Something else I've noticed is that I'm overtaking an MX5 as often as an MX5 overtakes me. Bearing in mind that I am Mr "Stay in the middle lane and do 65 mph to 70 mph" this seems to be missing the point of having a sports car somewhat, doth it not?

So that's this week's Fun Online Poll.

Vote here or use the widget in the sidebar.

Fun Online Polls: Midges and Tree diseases

With a reasonable turnout of 88 for such a left field question, the responses to last week's Fun Online Poll were as follows:

Have you noticed more midges than usual this summer?

No, fewer than usual - 42%
Yes - 36%
No, same as usual - 22%

That's me told then. I could have sworn there are/were more than usual, perhaps I was jsut unlucky this year. Or maybe it's very localised - more in some areas, fewer in others?
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Sticking with the nature theme, the BBC informs us that there is an "Unprecedented threat for UK trees from pests". Sub-text: boody foreign pests, coming over here, taking our jobs, killing our trees.

They list five such nasty diseases/pests, which one do you think sounds scariest?

Vote here or use the widget in the sidebar.

Never mind the cows...

... people are being attacked by trees in Swindon.*

A DOG-WALKER is worried for public safety after a second tree has come crashing down onto a path within two weeks... Mr Bennett is astonished the council has not acted to protect people from trees he thinks are suffering from dry rot.

The fallen tree comes just two weeks after Mr Bennett was featured in the Adver warning about the state of the trees following the fall of a large willow tree. He is amazed that no one was seriously injured or even killed, as the area is a popular spot with dog walkers and families...

A Swindon Council spokesman said: “We inspect trees that run alongside footpaths every three years and can find no record of problems with the willows in question...."

Every three years, huh? So he's not heard about the deadly tree virus spreading to other species?

* Spotted by Joseph Takagi

The USA has non-jobs too...

Via SPPI, this:
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Source: National Park Service [note: I checked yesterday evening to see if SPPI had copied the advert correctly, which they had, however the job advert has since been removed from the site, to be fair, this may simply be because the application deadline has passed]

Job Title: Interdisciplinary (Climate Change Adaptation Coordinator – Cultural Resources)

Department: Department Of The Interior

Agency: National Park Service

Job Announcement Number: NPSWASO-HQ-11-434393

SALARY RANGE: $89,033.00 – $136,771.00/year
OPEN PERIOD: Friday, February 04, 2011 to Thursday, February 17, 2011
SERIES & GRADE: GS-0101-13/14
POSITION INFORMATION: Full Time Career/Career Conditional
PROMOTION POTENTIAL: 14
DUTY LOCATIONS: 1 vacancy – Washington DC Metro Area, DC
WHO MAY BE CONSIDERED: This announcement is open to all U.S. Citizens.

JOB SUMMARY:

Experience your America and build a fulfilling career by joining the National Park Service. Become a part of our mission to unite the past, our cultures and our special places, to establish important connections to the present and build a rich and lasting legacy for future generations.

The National Park Service is seeking an energetic professional individual to serve as the Cultural Resources Climate Change Adaptation Coordinator. The position is located in Washington, DC and provides cultural resource management assistance to park units, and provides leadership and guidance to stakeholders in the cultural resource management and historic preservation communities nationwide on issues relating to climate change. Candidates interested in this position should have an indepth knowledge of climate change science either as a consumer or generator of climate change data and models to support decisions in cultural resource management and adaptation.

Quango Fun

According to the article at the BBC, there is going to be a joint action by Defra, the Forestry Commission, the Woodland Trust, Trees for Cities, the Tree Council, the London Tree and Woodland Community Grant, Civic Voice, NHS Forests, Keep Britain Tidy, the More Trees More Good campaign and The Big Tree Plant to get more trees planted.

Or possibly, it'll be a couple of Polish blokes in donkey jackets.

Trees

There's a merry old article in The Times about residents of Sandbanks in Poole, Dorset killing off trees on council-controlled property, or indeed their own gardens, in order to improve their views across Poole Harbour. The council is of course up in arms about this, wailing on about "mature trees protected by preservation orders".

Now, forgive me if I have misunderstood something here, but aren't councils supposed to do those things that benefit a majority of their residents, as decided democratically? Some people love having trees on their street (and ought to pay a few quid extra on their Council Tax to cover the cost of pruning them each year); other people hate trees - whether because they block the view; because they endanger foundations; or because they are allergic to them (and ought to pay a one-off precept to cover the cost of removing them), that isn't up to 'the council' to decide.

So shouldn't the council in this instance carry out a vote on each of the affected streets and go with whatever the majority says - be that preserving the trees at all costs,; chopping them down; scrapping the preservation orders or enforcing them even more vigorously?

The highlight of the comments is Mark B, who drifted completely off-topic at 12.:05 GMT on January 12:

In my village, on the Staffordshire / Cheshire boarder, they are considering letting someone turn an old farmstead into a wedding reception venue. This essentially destroys the property values, and quality of lives, of the whole community. It's just odd to me how Councils see business so favourably, but couldn't care less about homes and people's quality of life.

Too bloody right! That venue might create jobs for electricians, local DJs, taxi-drivers, florists, caterers, lap dancers and local hotels, who in turn create jobs for DIY shops, record shops, car repair workshops, petrol stations, delivery drivers, greengrocers etc etc. We can't have that sort of thing happening can we? Who knows where it might end - full employment or something? Pah! If you can't find a job or afford a house, can't you just emigrate* or something and leave England's countryside green, pleasant and unspoiled? I tell you, the youth of today ...

* PS, once you've emigrated, don't forget to keep paying voluntary National Insurance contributions back into the system to pay my pension. Bloody youth of today, shirking their responsibilities, leaving us pensioners to starve, no bloody respect...

And the trees are all kept equal ... by hatchet, axe and saw*

From The BBC:

A Christmas tree in the centre of Leeds has been felled on the advice of police amid safety fears about a demonstration planned for the weekend.

The tree, which cost taxpayers £2,000, went up two weeks ago in City Square. However, West Yorkshire Police advised the council it could pose a risk to the public during a planned march by the English Defence League on Saturday. Surprised commuters looked on as workmen used a chainsaw to cut down the 30ft tree early on Thursday morning.

The Islamists must be laughing themselves silly over this - what a result!

* That's a reference to a song by reactionary Canadian hard rockers Rush.

The World's Biggest Bonsai Tree

Climate Change: more irrefutable evidence

This otherwise uninspiring-looking tree/shrub type thingy, in the garden of the house we've been renting since early June 2008, did absolutely nothing at all until recently, when it suddenly sprouted large orange lumps, which look and taste remarkably like slightly unripe peaches. Or possibly apricots. Add that to the foxes digging deep holes to shelter from the heat, and there can be only be one conclusion...

That's not a Nazi tree ... these are proper Nazi trees!

Croydonian regales us with tales of a Nazi tree in Poland.

Pah, that's nothing! Feast your eyes on these babies ...

Full story here.