Is 50% of climate change caused by local land use change?

Are we missing half of the climate change picture by focusing on carbon? Might it be easier and more economically efficient to limit activities that affect the local climate through better planning and judicious use of economic incentive mechanisms?

Last week, I was in hallowed company in Davos, Switzerland, at the World Economic Forum meeting on 'climate change and tourism'. An excellent presentation from Shardal Agrawala of the OECD on the loss of snow from Alpine resorts showed declining trends eastwards - possibly indicating some local effects. Remembering the impact London has on Kent through its urban heat island, I canvassed the meterological experts there, asking what proportion of climate change in Europe [where temperatures have risen by 0.5% in the last century] is attributable to:

• global public goods/bads [i.e. greenhouse gases] and
• what is caused by local changes [i.e. urban sprawl, natural forest loss, pollution].

Resoundingly, the experts replied that around half is down to the global greenhouse effects and half to local land-use changes.

News to me. And I should think, news to the global debate over climate change mitigation. We can only wonder why this "fact" does not produce outrage among conservationists. Maybe my trust in these experts is misplaced - please let me know.

Significantly, such a "fact" necessitates a different sort of policy response - tax breaks/ incentives for natural forest restoration, green roofs, and urban trees; limits on city expansion; and research into how we can individually minimise our footprint [carbon, urban sprawl, etc] without rudely and wrongly telling others [often poorer people in developing countries] to limit their activities.

Is the science missing? Is the current answer more convenient? Is climate change actually a local phenomenon? Or is my head really in the clouds ...