Over the past few weeks, the environmental audit committee (EAC) has been interviewing scientists, climate change campaigners and others to determine whether the carbon budgets recommended by the Committee on Climate Change (CCC) are ambitious enough. I attended the EAC to give evidence with Professor Sir Brian Hoskins of the CCC. Brian is a leading UK climate scientist and has been working to convince people of the seriousness of climate change for over 30 years. This was our opportunity to explain why our carbon budgets are both ambitious and feasible.

The science of climate change increasingly shows that a 2C temperature rise will put us into a global danger zone. Already there are impacts being felt in some parts of the world. However, global emissions are increasing at a rate that means it is no longer possible to avoid 2C with certainty. The CCC's 2050 emissions reduction target is designed to maintain a 50-50 likelihood of keeping warming to within 2C, while also reducing the likelihood of an extremely dangerous 4C rise to very low levels. It is based on the latest science, including the consensus of the Intergovernmental Panel on Climate Change and more recent studies. Modelling work by the Met Office Hadley Centre suggests that our target can be achieved if global emissions peak before 2020, with a 50% cut by 2050 and further reductions afterwards.

Accepting that a cut of at least 50% is desirable, we then had to consider what the UK's contribution should be. In doing this, we looked at different models of burden sharing. In the end, we determined that it is difficult to imagine a global deal to cut emissions which allows developed countries to have emissions per person in 2050 which are significantly above a global average. Globally, we need to reduce emissions to an annual average around two tonnes per person in 2050, implying that the UK should reduce emissions by at least 80% relative to 1990 levels.

Our analysis suggested that a 42% cut in 2020 was sufficiently ambitious to put us on the path to an 80% cut in 2050. We argued that we should plan for a 42% cut, but should enact a lower but still ambitious cut of 34% before a global emissions reduction deal is achieved. We argued that only when other countries are fully committed to tackling climate change should we move to the higher level of ambition; this is the same approach adopted by the EU. We set out a range of measures to meet the 34% cut that would facilitate the transition to the 42% cut at the appropriate time.

In producing the carbon budgets, we analysed the potential to reduce emissions across the UK economy from power, transport, buildings, homes, agriculture and aviation. Domestic cuts of 80% can feasibly be made by firstly decarbonising electricity generation and then using this cleaner electricity for heat, transport and power. We estimate this will cost no more than 1% of GDP by 2020, or around £240 per person on average. There are "quick-wins" which could be achieved through making homes more energy efficient, and untapped potential which can be harnessed, for example, in the agricultural sector.

The government has recognised these opportunities and will next week publish its strategy for building a low-carbon future.

We realise that it is hard for people to imagine what such radical reductions might mean for their lifestyle in the future. In October, we will set out a much clearer picture of what we can all expect and what policies will be required to make this a reality. We are clear that a low-carbon model is the only one that will work in a future threatened by climate change. We are also clear that this won't mean people having to sit in the dark or not be mobile, or that everyone should become vegetarian. This is about living more sustainably, not limiting our growth or happiness.

What we need now is a clear plan of how we can achieve required cuts and create a more sustainable and secure future, and what opportunities there are for individuals and firms to make their contribution. We will be working with the government in the next months to ensure that such a plan is in place.

• David Kennedy is the chief executive of the Committee on Climate Change (CCC), an independent organisation set up under the Climate Change Act to advise the UK government on carbon budgets, targets and policies to tackly climate change