22/03/2015 18:25 GMT | Updated 22/05/2015 06:59 BST

Earth Hour: An Opportunity for All of Us to Demonstrate That We Care About Our Planet

'Little we see in Nature that is ours,

Getting and spending we lay waste our powers,'

- William Wordsworth, 1806

I've been an environmentalist for 25 years now.

I don't drive a car, I recycle all my recyclable rubbish, I use energy wisely, I think about the impact I am having on the planet in every decision I make ; I write letters to newspapers, I avoid flying whenever possible, I complain in over-heated, overlit, unnecessarily air-conditioned hotels ; I urge people to turn off their idling engines, I pick up endless dropped carrier bags to stop them getting into the rivers and seas and the bellies of sea creatures and I use my ever-dwindling celebrity status to promote conservation whenever I can.

Some people might think I'm a bit of a fanatic. Jeremy Clarkson would, no doubt, belittle my desire for a greener, healthier world for this and future generations by saying I'm an 'arty-farty, Lycra-clad cycling leftie-weftie who knits his own muesli' - or, more likely, would just punch me in the face.

But I don't care. Because I know that unless every one of us does our bit (and is clearly told what 'our bit' is), we face a very unpleasant future.

In the last two weeks, we've read reports about violent weather events caused by global warming, unparalleled air pollution in London, unprecedented water shortages in California, dangerously depleted fish stocks in British waters and the perilous state of the Great Barrier Reef.

If all this carries on unchecked, we will pay a heavy price, as crops and catches fail and waters and prices rise. There could be future conflicts over scarce resources. Everything we take for granted - clean air, clean, drinkable, abundant water and plentiful food could all be in very short supply. It doesn't matter how many cars we have in the drive or how cute the wallpaper is on our iPhone or how good our shellac nails look, without clean air, clean water and food, we perish. 'Simples!'

But around the world, millions of people are taking small steps towards living in a sustainable way that respects nature. Companies are investing in new technologies such as solar power and electric cars and are really thinking outside the box to help build a brighter future. People firmly believe that things can get better, and want be a part of the solution. Thanks to conservation efforts backed by millions, many species, including Pandas, are rediscovering the joy of sex and increasing their numbers accordingly. WWF now has over one million online followers in the UK alone. And all that makes me feel very optimistic.

But, as we approach the final weeks of another General Election campaign, my heart sinks. We hear a lot from our politicians and prospective politicians about the economy, about immigration, and about the health service but absolutely nothing about the environment.

Thanks to our thoughtlessness, our selfishness, our lust for profit at all costs (you can read that Wordsworth quote at the top of the page again now), the number of vertebrates in the world has dropped by half in just 40 years. Yes, read that stat again. By half. In 40 years. That shames every one of us. It's time for all the parties standing at this election to show some ecological backbone.

The next government - whoever they are - must, at the very least, begin to seriously de-carbonise our economy, continue to make homes and workplaces more energy-efficient and properly promote the development of renewables.

They must also tackle the issue of energy wastage which is all around us - in every unnecessary plasma screen burning away silently in every post office, on every railway platform and in every school and office reception. We are the problem and we are the solution. But we need leadership on this, the most important issue we have ever faced. Common sense, it seems, has become extinct.

By making the protection of the environment and the conservation of life of every kind on this planet of ours a central government policy and not just the preserve of a few 'politically correct' (horror !) individuals who 'don't wash and want the end of capitalism as we know it', then perhaps we will engage every parent in wanting to hand over the best gift of all to their children - a world in which those children can still eat, drink and breathe clean air.

Only such a strong and visible commitment to these basic tenets would give the UK Government any real moral force ahead of the Paris summit in December which will aim to reach a new global deal on climate change.

Even if climate change was a hoax perpetrated by the 'muesli-eating, lycra-clad cyclist lefties' - and it isn't - we'd still end up with more thriving new businesses, lower energy bills and cleaner air, if governments worldwide would only commit to loving our planet more than they love profit for profit's sake. Improving urban air quality alone could save up to £20 billion in avoided healthcare costs.

None of this will cost more than the failure to act which, over time, would cost the country billions. Economic growth requires the responsible stewardship of the natural resources that underpin every product we buy and sell. All the political parties are ignoring this basic fact and we need to remind them of that - before, during and after the election. We are in the deficit column on Nature's balance sheet and yesterday's budget with its backing for dirty fuels puts us even deeper into the red.

This week, the Welsh government took an important step towards creating a society in which people live within their means. In passing the 'Wellbeing of Future Generations Bill', it has committed all government bodies to use only a sustainable share of natural resources, rather than exploiting them to destruction.

So, in Wales, the environment will be stewarded in order that the country can keep providing the services that people depend on - water, food - and wild areas to simply enjoy. Other countries - including Sweden - have passed similar laws to good effect . This 'hair-shirtism' hasn't stopped the Swedes enjoying the best quality of life in the world.

Earth Hour, on 28 March, is an opportunity for all of us to demonstrate that we care about our planet. Switching off your lights for an hour from 8.30pm won't save the world (although being regularly more energy-efficient at home and at work would help hugely!) but it will hopefully help politicians to remember their repeated and unfulfilled promises to act on climate change and put green policies centre stage.

For many thousands of people, Earth Hour will be a first step towards thinking and acting with the environment in mind - as part of a world in which both people and nature can thrive.

Switch on your green-thinking and your heart - switch off your lights !

You can support WWF's priorities for the political parties - and ask your own local candidates what they will do about them - by visiting