In brief, on the issue of anthropogenic global warming (AGW) I am both a believer and a sceptic.  The available evidence overwhelmingly suggests that the world has been warming (with accelerated warming in the 1990s and then a stall afterwards, most likely due to the exceptional El Nino of 1998).  It also overwhelmingly suggests that human activity is contributing to this warming.  The serious question marks lie over how much of an effect human activities are having, and how the feedback systems will operate over the 21st century in response.

Climate models are the best thing we have to go by, and they overwhelmingly suggest a significant warming trend over the 21st century caused by greenhouse gas emissions.  But climate models rely upon the assumptions that are planted into them (the stronger the assumptions, the stronger the conclusions can be, but the more risk there is of them being heavily flawed).  Some of these assumptions include feedbacks involving water vapour and clouds that in reality are not well understood.   The fact that we have a strong consensus from these models is a compelling case for their accuracy, but as history has shown many times, if there's a consensus about something, it doesn't guarantee that it will be right.

Regarding what action we should take, I argue that we should focus on the wider socio-environmental-economic issue of working towards sustainable development and sustainable living, instead of just "tackling carbon emissions" or trying to maximise economic growth and consumption in the blind faith that unrestrained growth will solve all of our problems..  We will have to move away from systems that are based on continuous growth and towards systems that focus on sustaining a reasonable quality of living at minimal cost to the environment- we may need non-consumptive methods of fulfilment, such as inter-personal relatioinships to play a larger role relative to acquisition of material possessions than at present for example.  The reason is simple, even if it turns out that AGW has been seriously overestimated by the current generation of climate models, we are using up finite supplies of fossil fuels- the same behaviours that might be causing AGW are also non-sustainable for other reasons.  Yet we also need to sustain a decent quality of living for future generations and maintain decent levels of economic activity to enable future innovation and environmental progress to be cost-effective, so draconianism on the issue may be counterproductive.  This forms the basis for the environment section of my manifesto.  I also think established climate scientist Mike Hulme has some pretty good ideas on the subject.

One thing is clear- Cleadon's climate has changed significantly in recent decades, even in the period since I began recording.  Sunshine amounts have increased, frost and snow have become less frequent, temperatures have risen by at least 0.5C over the period since I started recording in 1993, and temperature homogeneity has increased (we get less switch-arounds than we used to, particularly in spring)..  Furthermore, records at nearby Met Office stations such as Durham University Observatory and Newcastle Weather Centre (which closed in October 2005) support this, and suggest that the early 1990s marked the beginning of an abrupt warming trend that started in the late 1980s.   Whatever the reasons, Cleadon's climate has definitely changed.