Global warming, Live 8 and others

Sir: I wish to take issue with Bruce Anderson's statements (Opinion, 4 July) that "our knowledge of the factors involved in climate change is still rudimentary" that "over the millennia there have been dramatic variations in the earth's climate, probably caused by the sun"; that "if scientists are unable to foresee the past, we are entitled to be sceptical about their attempts to explain the future" and that "the link between carbon emissions and global warming is still only a hypothesis".

By far the majority of scientists doing research on the earth's past, present and future climate agree that the climate is largely driven by changes in the amount of radiation received by the earth that are caused not by changes in the sun's output, but by subtle yet regular variations in the earth's orbit around the sun. Indeed, these variations are so well known that they can be projected far back into the past and shown to account for variations in the earth's sedimentary record and the ice ages. They can also be projected into the future to tell us when we might expect another ice age. Superimposed on these relatively big effects in the geological record are much smaller variations caused by tiny variations in the sun's output, and by the injection of dust high into the stratosphere during large volcanic eruptions.

Taking all of the natural variations into consideration, including observations of the behaviour of the sun over the past 100 years, we can calculate with a very high degree of confidence, using the most advanced numerical models, that the earth's climate should have cooled slightly overall during that period. Only by adding into those models the effects of man's injection of carbon dioxide into the atmosphere, caused by the burning of fossil fuels, can we reproduce the actual warming that has taken place over the past 100 years, and that is melting glaciers in the Arctic and the Antarctic at an unprecedented rate. That warming cannot be reproduced by any other means that we know of.

Perhaps Mr Anderson should consult credible scientists, like those at the UK's world-renowned Hadley Centre, before making bizarre pronouncements about climate science. It would be a pity if he continued to base his thinking on ignorance of the facts.

DR COLIN SUMMERHAYES

EXECUTIVE DIRECTOR, SCIENTIFIC COMMITTEE ON ANTARCTIC RESEARCH, SCOTT POLAR RESEARCH INSTITUTE, CAMBRIDGE

Live8: inspiration or self-indulgence?

Sir: Yasmin Alibhai-Brown's carping diatribe against Live8 (4 July) was in danger of suggesting that only those with a degree in development economics and a wholly virtuous and sustainable lifestyle can be allowed to support Make Poverty History. She also betrays a lack of understanding about the way a high-profile, media savvy event such as Live8 can act as a focus to harness and amplify the efforts of those who have been campaigning at the grassroots for decades. Unicef has understood this principle when it recruits celebrities as its goodwill ambassadors.

In my constituency, Make Poverty History mobilised children from 29 schools to make a 3km paper-chain that encircled the shopping centre. It encouraged hundreds to take part in an event with speakers and exhibits from Africa and around the world; it has built the support that has made Milton Keynes declare itself a Fair Trade City.

Live8 is part of that wider campaign. It extends the message of fair trade and better aid to people the campaign groups could never reach and it recruits them to the campaign. Instead of carping, Yasmin should welcome in everyone who will add strength to the pressure on the G8 leaders - and then engage with them to help them understand the complexities of the cause they have supported.

DR PHYLLIS STARKEY MP

(MILTON KEYNES SW, LAB) HOUSE OF COMMONS

Sir: Yasmin Alibhai-Brown struck the right note about Live8. This event is a stark reminder that we are drowning in a media-generated celebrity culture. Geldof et al are deeply embedded in a self-congratulating, narcissistic society of rich people and sycophants who have taken on a kind of messianic role in our culture.

ANTHONY MURPHY

SHIPLEY, WEST YORKSHIRE

Sir: The 30 UK trade unions that have signed up to the Make Poverty History coalition will have been shocked to hear that media pundits have cast this unique movement as nothing more than a shallow vehicle for celebrities and politicians to shed their guilt.

More than 550 million working people are counting on this "glib" campaign to pile enormous pressure on the G8 to lift them out of poverty. Millions of children are counting on this "superficial" campaign to get them out of dangerous work and into school.

Global trade union leaders representing 170 million workers met with the Prime Minister to tell him that working people across the world back his efforts on poverty are decent work and trade unions are a vital part of the solution.

BRENDAN BARBER

GENERAL SECRETARY, TRADES UNION CONGRESS, LONDON WC1

Sir: After the weekend's various activities marking the forthcoming G8 summit, one has to wonder if the Live8 concerts actually helped focus the world's attentions on the problems of the third world or was a distraction.

I was one of an estimated 225,000 people who came from across the country to march in Edinburgh for the well established Make Poverty History campaign. In contrast around the same number of people stood in a park in London and watched a pop concert. The media inevitably took the easy route and focused on the concert.

The attention given to Live8 (and even more barmy events such as Sail8) inevitably acts as a distraction from the less frivolous and deeper-rooted work of the Make Poverty History campaign. At Edinburgh, it was great to be able to listen to the voice of ordinary Africans. Their words are worth a thousand lyrics from Bob, Paul, Sir Elton and the rest.

NEIL BRADBURY

PRUDHOE, NORTHUMBERLAND

Sir: I read with amazement your front page headline "Now on to Edinburgh " (4 July). I am sure that the 225,000 people who had travelled from all parts United Kingdom and indeed the world to take part in the Make Poverty History rally and march on Saturday will be equally surprised. Saturday was a wonderful day of mass protest culminating at three o'clock with a minute of absolute silence in solidarity with all those who do not live our very privileged lives.

NORMA DANIELS EMM

EDINBURGH

Sir: The "Marshall Plan" of aid flow to Africa is all good but the question to ask is, "How much of this aid will actually trickle down to the needy?" One can only imagine that a substantial portion will get pocketed by the corrupt, some will find its way back to G8 countries through consultants/projects and the rest used to sustain the expensive lifestyles of the local and expat NGO bosses.

What Africa really needs is true empowerment. G8 must endeavour to lift barriers to African trade by tackling farm subsidies at home that have hit hard at several agricultural sectors in African countries. Everything else is lip-service.

NIMISH HADOLE

NAIROBI, KENYA

Sir: What a sorry picture (4 July) of the aftermath of Live8. How sad that those attending have left one of our finest London parks looking worse than something from the third world because of their inability to take their rubbish home. Surely it is not beyond anyone to put a plastic bag in their pocket when setting out for one of these events and use it to leave the venue clean and tidy. A caring society? Maybe, but also very dirty.

JENNY CODRINGTON

BEDFORD

These electric cars are no paralytics

Sir: L K J Setright has a point when he refers to the on-board engine and gearbox of the hybrid car as a "messy complication" ("Hybrids are not up to the job", 28 June). However, it is certainly an exaggeration to claim that "carrying substantial storage batteries is what makes all electric vehicles paralytics" or that "all present modes of storing electrical energy are inadequate".

The latest battery electric vehicles (EVs) use relatively light lithium ion batteries, which provide a driving range and maximum speed that is more than adequate for average urban use. And with better acceleration than many petrol and diesel cars, EVs are anything but sluggish, as evidenced by electric sports cars such as the Fetish and T-Zero. Most importantly, EVs offer the opportunity to greatly reduce pollution, especially when they are charged with renewable electricity.

RALPH LOVESY

CAMPAIGN FOR BATTERY ELECTRIC VEHICLES, LONDON E1

Courts out of touch over cannabis

Sir: In view of the new popularity of cannabis revealed in Terry Kirby's excellent report on DIY druggery (28 June), perhaps those in a position of influence may care to point this out to the magistrates and judges who are still sending people to prison for dope offences.

Kirby's report shows that a large section of the electorate plainly believes cannabis not to be the seed of the Antichrist which its opponents make it out to be and so wouldn't it be fun and fab if the judiciary took the risk of conforming with public opinion?

Sending anybody to prison for enjoying a drug that now has the toxic status of little more than a sherbet sweet serves only to introduce these unfortunates to far more harmful narcotics.

GEOFF BAKER

ALL CANNINGS, WILTSHIRE

Metropolitan Games

Sir: On Wednesday, London is set to hear if London has won its bid to host the 2012 Olympic Games. Regardless of the result am I the only person hoping that the result of the London bid will be reported in London only?

J POWELL

BEDFORD

Psychiatry helps

Sir: The Royal College of Psychiatrists welcomes Raj Persaud's thoughtful and informative editorial (30 June). The Church of Scientology has always been vehemently opposed to orthodox psychiatry and it has always been fruitless to respond or to enter into any dialogue with them in relation to their claims. Whilst we respect the rights of people to have their own views, to frighten and deter people from seeking help when they desperately need it is dangerous. Psychiatry has helped millions of people with its treatments and therapies, which are closely regulated like all medical professions.

DR TREVOR TURNER

VICE-PRESIDENT, THE ROYAL COLLEGE OF PSYCHIATRISTS LONDON SW1

Hambling's scallop

Sir: May I scotch Michael Church's airy assumption that local people who oppose the installation of Maggi Hambling's scallop shell on the beach north of Aldeburgh are philistine (Classical Diary, 28 June)? Our basic objection is not to the work itself but to its siting. A landscape defined as being of outstanding natural beauty and special scientific interest has become overrun by tourists curious to explore a man-made object. People used to walk the empty north beach to savour the curve of the shoreline and the long vistas of sea and sky. No longer!

HUMPHREY BURTON

ALDEBURGH, SUFFOLK

Cathedral turnstiles

Sir: I am not a member of a church and have no objection to paying to view our cathedrals (letters; 30 June, 1 July). They are important buildings which obviously must be maintained, which is expensive, and visitors should pay as they do when visiting similar secular buildings. Perhaps active church members could be exempted by carrying a pass issued by their local church leader if they are too mean to pay.

TREVOR ROBERTS

BARKING, ESSEX

Youth on the spot

Sir: Headline on Ceefax today: "Teenagers face spot fines at home." Surely Blairite prejudice against young people has reached its acne?

COLIN V SMITH

RAINFORD, MERSEYSIDE