future, as social and ecological forces interact with one another, causing disruptions from the local to the global scale. What will happen if we push our planet too far? We can’t


say yet for sure. But the mounting evidence all around us— from droughts, forest fi res, and melting glaciers (due to climate change), to massive loss of biodiversity and threats to water supply (due to cutting of rainforests), to catastrophic fl oods of urban landscapes like New Orleans during Hurricane Katrina— off ers no grounds for hesitation.4


Faced with increasingly clear


risks, we now realize that it is becoming too expensive not to respond. That is why the heart of our Human Quest must be to sustain the ability of all ecosystems, or biomes,5


to support the modern


world and its future development. To a large extent, this also means preserving and nurturing the beauty of our planet. Our strategy for success must also lead us to cherish and respect nature’s richness. The more colorful and alive a natural system is, the more it serves our needs for human wellbeing. The more functional type of plants and animals in a forest, grassland, or lake, the higher the redundancy of its critical parts and the larger its resilience to unwanted shocks and stresses. Changing our ways will not be easy. It will require transforma- tions in economies, societies, cultures, and patterns of con- sumption and production—a full revolution in our relationship with Earth. We must replace the prevailing societal paradigm, in which we perceive ourselves as being apart from our natural surroundings, to one in which we are deeply intertwined with all of the planet’s systems. We cannot survive without nature, though nature can surely survive without us.


HEADING IN THE WRONG DIRECTION We are often led to believe that climate change is the only global environmental threat to human well-being. Unfortunately, scien- tifi c observations clearly show that more, much more, is at stake. Over the past 50 years, our growing numbers and unsustainable habits have dramatically increased environmental pressures in many ways. No matter which parameter you choose that matters for human wellbeing, they all look the same, with a sharply rising curve in the wrong direction (Figure 1.1). In fact, as we will argue in this book, solving the global climate crisis—a Herculean task in its own right—may turn out to be easier than many of the


These curves show that acceleration in the following: (A) rise in atmospheric CO2 fuel burning, (C) atmospheric CH4


other looming global environmental challenges facing humanity in the coming decades. What these charts show is that all environmental processes


(both ecological and biophysical) that determine the well-being of individuals, communities, and nations, show accelerated negative trends over the past 50 years. These include the major challenges of human-induced climate change, mass extinction of species, land and water degradation, the nutrient overload of our freshwater systems and coastal ecosystems, and air and chemical pollution. We also urgently need to understand that, of all these


environmental changes, the loss of biodiversity is the most dan- gerous for our own development. The fact that more than 9,000 plant species and over 10,000 animal species6


are endangered is


shocking in its own right. But it is also a threat to our own development. Biodiversity provides us with »ecosystem services« —such as clean drinking water and crop pollination—that in turn drive the modern economy. Nature’s richness furthermore builds a kind of insurance for us, providing us with resilience to deal with shocks and stresses such as large disease outbreaks, droughts, and fl oods. The value of the natural world is incredibly diffi cult to defi ne.


The prospect of losing such important and beautiful species as mountain gorillas, tigers, Gentoo penguins, and orcas makes us sad at heart. But it is possible to put an economic value on the basic ecosystem services provided by nature. In fact, the net value of these services surpasses the combined gross domestic products of 196 countries in the world.6B Another diff erence between biodiversity loss and most other


environmental threats is that once a species like the Orangutan, Jameson’s Green Mamba or Tomato Clownfi sh is lost, it is gone forever. The loss is absolute. There is no repair, and no substitute, as there is for most other problems we face. To be honest, it is bizarre that we have not understood this earlier. It is as if we would accept losing a cathedral like Notre Dame in Paris without blinking. But we are willing to accept the loss of entire species. We can rebuild a cathedral, but we cannot reinstate a species that we have sacrifi ced for short-term economic gain. Today, we lose species on the planet 100 to 1,000 times faster


than evolution calls for. This raises our current era to a classi- fi cation as one of global mass extinction. We do not know what we lose for the future, each time we eradicate an animal or plant.


concentration from human emissions, (B) atmospheric N2 O concentration from agriculture and fossil concentration from expansion of livestock production systems, (D) percentage ozone loss over Antarctica due to our emissions of ozone depleting


chemicals (E) average temperature anomalies in the northern hemisphere, (F) natural disasters after 1900 resulting in more than 10 people killed or more than 100 people affected, (G) percentage of global fi sheries either fully exploited, overfi shed or collapsed, (H) annual shrimp production as a proxy for coastal zone alteration, (I) estimate of human caused changes in nitrogen pollution of coastal areas from the period since 1850, (J) loss of tropical rainforest and woodland, as estimated for tropical Africa, Latin America and South and Southeast Asia, (K) amount of land converted to pasture and cropland, and (L) calculated estimate of rate of extinction of species on Earth (Steffen et al. 2004 and 2012)


29


THE BIG PI CTU R E


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