With consistently huge viewing figures - the opening two episodes alone drumming up 12 million viewers each - the BBC's Frozen Planet has captured the nation's imagination. It's not hard to see why - from jousting narwhals and synchronised killer whale hunts to men scaling vertigo-inducing cliffs in pursuit of bird eggs, the series has offered an amazing insight into the lives of the people and species that make the Polar Regions their home.

This evening, the series bows out with an episode addressing the impacts of climate change on the Arctic and Antarctica. And with the latest round of UN climate negotiations drawing to a close in Durban at the weekend, it should serve as a timely reminder of what we stand to lose if global warming continues unchecked.

Having spent more than two and a half years in Antarctica during my time with the British Antarctic Survey (BAS), and been to the Arctic in my capacity as Polar Policy and Programme Manager at WWF-UK, I've seen both regions first hand. And although the programme has clearly illustrated the beauty of the polar wilderness, capturing the sheer scale of these regions is a far harder task.

The Arctic sprawls across 30 million km2, and Antarctica covers approximately 58 times the area of the United Kingdom. These vast regions play a vital and unique role in maintaining the biological, chemical and physical balance of the globe. As well as absorbing carbon dioxide from the atmosphere, making them an important 'carbon sink' that could be threatened by rising temperatures, the polar regions also play a key role in driving the powerful ocean currents that circulate warm and cold water around the world. Both regions also have the potential to contribute to a large rise in global sea-levels. For example, British Scientists are currently investigating the very remote and inaccessible Amundsen Sea Embayment ice sheet in West Antarctica, which may be becoming unstable. The recent pattern of thinning could be a precursor to wholesale loss of the ice sheet, implying a sea-level rise of around 1.5 metres.

There can be no doubt that the Arctic and parts of Antarctica are warming rapidly.

Temperatures on the west coast of the Antarctic peninsula have risen by nearly 3°C in the last 50 years and the Arctic has warmed at least twice the global average in the same timeframe. Nearly 40 percent of the Arctic sea ice area that was present in the 1970's was lost by 2007 (the record low for summer sea ice extent). Reduced sea ice amplifies warming, stimulating further melting and the Arctic Ocean is now predicted to be virtually ice-free during the summer within a generation.

So clearly the impacts of climate change in the Polar Regions mustn't be ignored or underestimated, both in themselves and as forerunners of wider global climate impacts. We need to make sure we are responding to these threats appropriately, by pushing for a global agreement to mitigate the worst of our carbon excesses, and by ensuring that we can adapt appropriately to those impacts we can no longer avoid.

WWF is working on both these fronts, and in many ways, this last episode of Frozen Planet should provide a neat and powerful answer to anyone who questions why WWF, a charity known primarily for its work on wildlife, considers climate change to be a priority. The incredible natural world that the series has showcased is demonstrably under threat from global warming. And as an organisation with conservation at its very heart, it is key that we work to highlight the effects of climate change, and limit its impacts on some of the worlds most iconic species and fragile landscapes.

We currently have a team at the UN negotiations in Durban, lobbying for strong and urgent emissions reduction targets and a global adaptation fund, while out in the field, our polar experts are trying to find the best solutions to tackle problems on the ground. In Antarctica, for example, we are collaborating with French and British scientists to track the ice-dependant Adélie penguins. The data will be used to identify biodiversity 'hot-spots', develop habitat models and fisheries management approaches for the region in the context of a warming climate

Meanwhile, in the Arctic, we have been working with scientists and local people on an innovative new scheme that aims to locate the areas of the region that seem most likely to show resilience in the face of climate change. The Rapid Assessment of Circum-Arctic Ecosystem Resilience (RACER) assesses the future capacity of the region to adapt, rather than solely focussing on the areas that we already know are vulnerable now. It aims to help inform decisions as to which areas will need most protection in future, focus conservation and management attention on the importance of minimising environmental disturbance in specific areas, and to establish how a functioning Arctic ecosystem can be maintained in a warming world.

With the UK recognised as one of the non-Arctic nations with greatest interests in the Arctic, from shipping and science to insurance and mineral extraction, we have an important role to play in stewardship for the region. So WWF-UK is also working with other NGOs (FoE, RSPB, Greenpeace, MCS, the UK Youth Climate Change committee and the Whale Dolphin and Conservation Trust) and key Arctic experts, to draw up a set of Arctic principles, outlining how the UK government can make sure that any British involvement in the region is carefully managed. We hope that by adopting these principles, from ensuring that shipping and fisheries are sustainably managed to playing a part in regulating onshore and offshore mineral extraction effectively and to a very high standard, the UK government can finally start to live up to it's 'greenest government ever' promises.

As for the millions of people who've watched and enjoyed Frozen Planet - this final episode may leave them with a clearer understanding of the very real threat that climate change poses to our beautiful and fragile polar regions. Because while it's important that the UK government takes responsibility for our nation's activities in these great wilderness regions, we also need to ensure that we are doing our utmost to limit greenhouse gas emissions on our own turf. It is vital that we realise sooner rather than later that our actions at home can have an impact, even on the frozen ends of the earth.