Does climate cloud the bigger picture?
OK. So it's a big question for a Friday afternoon, I know - particularly on a London summer's Friday afternoon that sees the greatest male tennis player in history and the best UK player in a lifetime treading Wimbledon's green swards, and the mighty Blur reuniting for an evening's Britpopping in Hyde Park; but it's with me despite all this, along with a desire to share.
The question is this: how should society prioritise the world''s various environmental woes?
The political space - no doubt about it - is crammed full of climate change.
When you talk about this to people working in other fields - the decline in global biodiversity, the spreading of deserts, the depletion of our oceans - you tend to get two batches of opinions about whether that domination is justified.
One opinion holds that climate change threatens to worsen all other environmental ills to such an extent that it makes sense to prioritise it; and raising its profile will in the end focus attention on all the other issues too.
The other bemoans the comparative lack of attention given to all else in comparison with climate change.
A couple of things have had me mulling the question this week.
First off was a workshop I took part in at the World Conference of Science Journalists in London on the reporting of climate change.
One of the points I raised was that if you look at the biosphere's most recent health check - the UN Global Environment Outlook (GEO-4) report from 2007 - it's obvious that climate shifts are far from being the only kind of environmental trend.
Andy Revkin of the New York Times was also speaking; and he began his talk (as he begins the blurb for his dot.earth blog) by recalling that within a lifetime there will be nine billion people on the planet's surface, all clamouring for its sustenance.
I resurrected, for this workshop, a slide I made a couple of years ago, an attempt to link some of the major environmental trends and their drivers schematically; I've pasted it below.
So whereas we see climate change (the smoke picture) driving water shortages and desertification, we see that deforestation (the tree at bottom left) currently drives climate change more than climate change drives deforestation.
Climate change is projected to become a major driver of biodiversity decline (the cute furry face); but at the moment, the major factor is habitat loss as the human footprint expands.
When it comes to fisheries (forgive the rather gruesome shark head picture), the single biggest driver is undoubtedly over-consumption of what nature provides - the over-use of resources, which also drives climate change and deforestation and just about everything else.
And underlying it all is the growth in the human species.
Have I got this right? I think so - no-one's commented adversely whenever I've brought it forward - but I'll await comment and criticism gladly.
The second thing that brought the question into my head was a party to mark the 85th birthday of Maurice Strong, who (among many other accomplishments) chaired what's commonly cited as the world's first true environment summit, the Stockholm Conference on the Human Environment in 1972.
A few months ago I was reading some material about Stockholm, and it was fascinating to see what issues were prioritised then, and what's changed since.
Fallout from atomic bomb tests, chemical pollution, the expanding human population, whaling, and how urban life could be made sustainable and bearable against the projected expansion of cities - these were all prominent then, with few nods to climatic change or the global loss of species.
In part, priorities have changed with the geopolitical world. Atomic bombs (or as we call them now, nuclear weapons) are no longer tested in open air - in most nuclear states, they're hardly tested at all - and President Obama now holds out the prospect of culling their numbers to levels unimaginable during the period when the concept of Mutually Assured Destruction penetrated far enough into the zeitgeist that rock stars wrote anthems about it.
Science has advanced since then, which has brought bigger declines, better analyses of the problems and a wider range of ideas for solving them. Cleverer fishing methods accelerated the fall in commercial fish stocks; and now clever zoologists are plotting ways to restore some of the degraded species.
Substitutes have been found for some of the most damaging synthetic chemicals, and other regulated out of use.
These trends explain some of the changing priorities. But other changes are less obvious: why, for example, has population growth gone away as a subject of discourse?
I've tried to find rational ways of figuring out answers to the prioritisation conundrum.
One sample question is this: if climate impacts are at present largely reversible but the loss of a species self-evidently isn't, does that make biodiversity loss more important than climate change?
Another is this: if environmental issues are so interlinked, then why do we bother separating them out in the way that the Rio conventions do? Woudn't it be more logical to try to sort everything out en masse?
A third is this: if the fundamental drivers of all the trends are the swelling in the human population and our expanding thirst for raw materials, why aren't these the things that politicians and environmental groups are shouting about and trying to change?
I don't have the answers to any of this; I'm not even sure if such a thing as the "right" answer exists, still less whether a way of finding it logically can be discovered.
Perhaps explanations will be found in cultural and political values rather than logical assessment.
But I think it's important that we at least discuss the point, not least for the very practical reason that some of the policies being considered as a response to climate change - such as biofuels, and carbon sequestration through forestry and ocean fertilisation - could exacerbate other environmental problems.
The weekend awaits; and a glorious one it promises to be here in London. Strawberries and cream, and a double dose of Parklife, may be the immediate priorities.
I look forward to seeing what you've made of the longer term ones by the time a new working week opens for business.