Human population growth, refugees & environmental degradation

7 07 2017

refugeesThe global human population is now over 7.5 billion, and increasing by about 90 million each year. This means that we are predicted to exceed 9 billion people by 2050, with no peak in site this century and a world population of up to 12 billion by 2100. These staggering numbers are the result of being within the exponential phase of population growth since last century, such that some 14% of all human beings that have ever lived on the planet are still alive today. That is taking into account about the past 200,000 years, or 10,000 generations.

Of course just like the Earth’s resources, human beings are not distributed equally around the globe, nor are the population trends consistent among regions or nations. In fact, developing nations are contributing to the bulk of the global annual increase (around 89 million per year), whereas developed nations are contributing a growth of only about 1 million each year. Another demonstration of the disparity in human population distributon is that about half of all human beings live in just seven countries (China, India, USA, Indonesia, Brazil, Pakistan, Nigeria, and Bangladesh), representing just one quarter of the world’s total land area. Read the rest of this entry »





Where do citizens stand on climate change?

2 01 2017
Talk to the hand

Talk to the hand

Climate change caused by industrialisation is modifying the structure and function of the Biosphere. As we uncork 2017, our team launches a monthly section on plant and animal responses to modern climate change in the Spanish magazine Quercus – with an English version in Conservation Bytes. The initiative is the outreach component of a research project on the expression and evolution of heat-shock proteins at the thermal limits of Iberian lizards (papers in progress), supported by the British Ecological Society and the Spanish Ministry of Economy, Industry and Competitiveness. The series will feature key papers (linking climate change and biodiversity) that have been published in the primary literature throughout the last decade. To set the scene, we start off putting the emphasis on how people perceive climate change.

Salvador Herrando-Pérez, David R. Vieites & Miguel B. Araújo

“I would like to mention a cousin of mine, who is a Professor in Physics at the University of Seville – and asked about this matter [climate change], he stated: listen, I have gathered ten of the top scientists worldwide, and none has guaranteed what the weather will be like tomorrow in Seville, so how could anyone predict what is going to occur in the world 300 years ahead?”

Mariano Rajoy (Spanish President from 2011 to date) in a public speech on 22 October 2007

Weather (studied by meteorology) behaves like a chaotic system, so a little variation in the atmosphere can trigger large meteorological changes in the short term that are hard to predict. On the contrary, climate (studied by climatology) is a measure of average conditions in the long term and thus far more predictable than weather. There is less uncertainty in a climate prediction for the next century than in a weather prediction for the next month. The incorrect statement made by the Spanish President reflects harsh misinformation and/or lack of environment-related knowledge among our politicians.

Climate has changed consistently from the onset of the Industrial Revolution. The IPCC’s latest report stablishes with 95 to 100% certainty (solid evidence and high consensus given published research) that greenhouse gases from human activities are the main drivers of global warming since the second half of the 20th Century (1,2). The IPCC also flags that current concentrations of those gases have no parallel in the last 800,000 years, and that climate predictions for the 21st Century vary mostly according to how we manage our greenhouse emissions (1,3). Read the rest of this entry »





Bad science

10 02 2016

Head in HandsIn addition to the surpassing coolness of reconstructing long-gone ecosystems, my new-found enthusiasm for palaeo-ecology has another advantage — most of the species under investigation are already extinct.

That might not sound like an ‘advantage’, but let’s face it, modern conservation ecology can be bloody depressing, so much so that one sometimes wonders if it’s worth it. It is, of course, but there’s something marvellously relieving about studying extinct systems for the simple reason that there are no political repercussions. No self-serving, plutotheocratic politician can bugger up these systems any more. That’s a refreshing change from the doom and gloom of modern environmental science!

But it’s not all sweetness and light, of course; there are still people involved, and people sometimes make bad decisions in an attempt to modify the facts to suit their creed. The problem is when these people are the actual scientists involved in the generation of the ‘facts’.

As I alluded to a few weeks ago with the publication of our paper in Nature Communications describing the lack of evidence for a climate effect on the continental-scale extinctions of Australia’s megafauna, we have a follow-up paper that has just been published online in Proceedings of the Royal Society B — What caused extinction of the Pleistocene megafauna of Sahul? led by Chris Johnson of the University of Tasmania.

After our paper published earlier this month, this title might seem a bit rhetorical, so I want to highlight some of the reasons why we wrote the review. Read the rest of this entry »





It’s all about the variation, stupid

12 01 2015

val-1-3It is one of my long-suffering ecological quests to demonstrate to the buffoons in government and industry that you can’t simply offset deforestation by planting another forest elsewhere. While it sounds attractive, like carbon offsetting or even water neutrality, you can’t recreate a perfectly functioning, resilient native forest no matter how hard you try.

I’m not for a moment suggesting that we shouldn’t reforest much of what we’ve already cut down over the last few centuries; reforestation is an essential element of any semblance of meaningful terrestrial ecological restoration. Indeed, without a major commitment to reforestation worldwide, the extinction crisis will continue to spiral out of control.

What I am concerned about, however, is that administrators continue to push for so-called ‘biodiversity offsets’ – clearing a forest patch here for some such development, while reforesting or even afforesting another degraded patch there. However, I’ve blogged before about studies, including some of my own, showing that one simply cannot replace primary forests in terms of biodiversity and long-term carbon storage. Now we can add resilience to that list.

While I came across this paper a while ago, I’ve only found the time to blog about it now. Published in PLoS One in early December, the paper Does forest continuity enhance the resilience of trees to environmental change?1 by von Oheimb and colleagues shows clearly that German oak forests that had been untouched for over 100 years were more resilient to climate variation than forests planted since that time. I’ll let that little fact sink in for a moment … Read the rest of this entry »





The climate of climate change

4 09 2012

The primary scientific literature on climate change spawns hundreds of debates on an array of topics. When the technical debate among experts, and the obvious uncertainties, are taken up by the media, they are typically treated as any other topic, which ends up in some people not trusting science and others exploiting the ‘debate’ for their own interests.

Many media debates consist of one moderator and several speakers with two confronting views. When the topic under discussion affects our daily life (e.g., unemployment), the average spectator will often agree with one of the views. When the topic affects people (apparently) in a general fashion (e.g., climate change), the spectator might distrust or simply ignore both views. Thus, the media shapes public opinion such that people’s perception of the news becomes black, white, “I don’t believe it” or “it doesn’t exist”. Public debates on climate change are like a ‘contact sport’ (1), a team has to win in a contest where both parties alternate attack and defence. The participation of speakers without specialised expertise on climate change, especially if they represent short-term political and economic interests, instigates public mistrust and inhibition (2). This situation erodes the informative role that science and scientists must play in the creation of novel environmental policies aiming to improve the present and future wellbeing of our society (3, a Science paper unsurprisingly challenged by US administration’ bastion Fred Singer: 4). Read the rest of this entry »





Who’s responsible for climate change? Not ecologists, right?

19 06 2012

It’s sometimes difficult to take a long, hard look in the mirror and admit one’s failings. Today’s post is a thought-provoking challenge to all ecologists (indeed, all scientists) who gaily flit all over the known universe in the name of science. I’m certainly in one of the upper guilt echelons on this issue – and while I tell myself each January that “this year I’ll fly much less frequently”, I usually end up breaking my resolution by month’s end.

In some defence of my sins, I have to state that while I should always endeavour to fly less, I am convinced that strategic, well-planned (and usually small) meetings are some of the best ways to advance scientific ideas. As CB readers might know, I am particularly impressed with the results of dedicated workshops in this regard.

I also think that even if all aeroplanes suddenly fell from the sky and one could no longer enjoy that transcontinental G & T, we’d still be in a terribly climate-change mess – we need BIG solutions beyond simple consumption reduction.

Now I’m just making excuses. Thanks again to Alejandro Frid for providing this challenge to me and our colleagues.

Recently I asked a math savvy graduate student at Simon Fraser University, in Western Canada, to proofread an equation. ‘No problem’, she replied, ‘but could you wait a few days? I am about to fly to Korea for a conference but I will return shortly.’

Hmmmm? So this is what the system promotes: gallivanting halfway around the world and back within a week, burning extraordinary amounts of fossil fuels, all in the name of scientific career advancement. Who are the climate change culprits? Not us ecologists, right?

Of course I am being unfair to Ms. Maths Savvy. Most of us are equally guilty of boarding that big ol’ jet airliner in the name of scientific meetings or the pursuit of ecological knowledge in far off study sites. Yet the inconvenient truth, according to a recent editorial in Nature Climate Change1, is that “international air travel accounts for about 5% of global warming”. Flying all over the world in the name of ecology and conservation therefore implies that we believe that (i) there are no alternative means to accomplish the same goal with far less emissions, and (ii) that the benefits of our work outweigh the atmospheric impacts of flying. Think again.

For insight into these issues, I interviewed Kevin Anderson, deputy director of the Tyndall Centre for Climate Change Research at the University of Manchester and arguably the climate conscience of scientists. I was attracted to Anderson’s perspective because of its blunt honesty. He calls air travel “…the most emission profligate activity per hour”2 and has little patience for the irony that “international climate jamborees”, otherwise known as climate science meetings, have contributed far more to increasing carbon emissions than to any meaningful action on climate change. His recent commentary in Nature3 makes it amply clear that buying carbon offsets when flying may ease our perceived guilt but not emission rates. Read the rest of this entry »