They're nagging us about global warming again. Panorama (BBC1) mapped the experiences of Justin Rowlatt, whose BBC boss told him and his family to "go green for a whole year". This didn't stop Justin from flying to Jamaica, ostensibly to investigate carbon offsetting. And he found it was futile to fit a wind turbine on his house and too expensive to install double glazing or loft insulation. The programme still tried to make us feel guilty because our houses supposedly account for a quarter of Britain's carbon emissions.

Still, Rowlatt did things like installing low-energy light bulbs and hence acquired the title of 'ethical man'. One reason I hate these sermons about climate change is the way they pervert the language. You might think that an ethical man would love his neighbour as himself and forswear violence, but nowadays being ethical merely seems to involve weeing in the compost. And why do environmentalists boast that they are "saving the planet" when they just turn the central heating down?

Thank heaven for programmes like The Great Global Warming Swindle (Channel 4), which questioned the prevailing orthodoxy about global warming. It pointed out that our climate has always changed without human intervention, and perhaps that is what is still happening.

Many people say they are concerned about the effect of global warming on future generations, while seemingly unaware of the dangers that children already face on a daily basis. My Life as a Child (BBC2) returned for a new series in which children are given video cameras to tell us about their lives. The first episode was entitled Normal Families - perhaps ironically, as the three families filmed by three separate girls showed how 'normal' families can damage children.

Katie (eight) from Chesterfield said: "My Mum has split up with my Dad" - and told us how they don't like talking to one another, so they just text each other. Katie's ninth birthday arrived without any contact from her father, and Katie went from saying "I'm not sure if Dad loves me" to "He hates me, that's what I think".

Molly (11) from Bognor has parents who also don't get on, although they stay together in thinly-veiled hostility - and this clearly upsets Molly. Erin (eight) from Chelmsford is different - not only because her (unmarried) parents live happily together but because she's a self-confessed tomboy who worryingly loves fighting and asserts: "You need to be tough." Altogether, this was a sad programme, although there was a cheerful moment when Erin's tooth fell out. She lost the tooth but wrote a note to the Tooth Fairy which suggested: "If you could still give me some muny I wold apresaat it."

The programme was interesting but distracting - jumping to and fro between the children, instead of telling their stories one at a time. The insulting implication is that we all have short attention spans.

Moving to programmes about art, Rolf on Lowry (BBC1) was, like most of Rolf Harris's art programmes, heart-warming and inspiring. Rolf looked beyond the conventional image of L.S.Lowry as a painter of industrial landscapes and matchstick people, surveying his pictures of such places as Berwick-on-Tweed, the Lake District and the North Sea. Rolf didn't only describe Lowry's life and work but he stopped to chat with passers-by and was inspired to paint some of Lowry's haunts.

The South Bank Show (ITV1) interviewed Mark Wallinger, who has created some very strange artworks, including 'video installations' (the poor man's TV shows). His latest work is more thought-provoking: reproducing at Tate Britain the mass of banners, posters and photos that the police confiscated from Brian Haw's protest site outside the Houses of Parliament. Melvyn Bragg tried hard to question the value of the work (for example, telling Wallinger that he ought to be protesting at Muslim extremists rather than our Government) but Wallinger's exhibition at the Tate commendably underlines the stupidity of the 'exclusion zone' around Parliament - and the way that our freedoms are being threatened.