Earth’s forests are extremely important for biodiversity, the global economy, and weather patterns worldwide. Trees provide habitat for other plants, animals, microbes, and so on, and large forests can influence weather by releasing large volumes of water vapour into the atmosphere. On top of this, global forests uptake large quantities of CO2 from the atmosphere, helping to offset the release of CO2 from fossil fuel emissions. One issue however, is that humanity has been engaged in global deforestation for quite some time now. In a recent issue of Science, Hansen et al. (Hansen et al. 2013. Science 342:850) examined global forest loss across the planet from 2000 to 2012 using satellite mapping of the globe.
Overall, tropical forests were the hardest hit: over 700 million square kilometres of forest were lost over the 12 years. The worst levels of deforestation were seen in Brazil, where forest lost exceeded 40,000 km2 per year. Forest fires in the boreal forests (think northern Canada, Europe, Asia) drove a decline in forest cover, and this could get worse in the coming decades as forest fires are expected to increase. There is good news however, Brazil has implemented forestry management practices that have reduced levels of deforestation by over 50% down to ~20,000 km2 per year.
As a species, we are finally capable of visualizing exactly how much influence we have on our environment. We can see that Earth has lost ~2.3 million km2 of forest cover over the past 12 years (~1/4 of the area of the United States). Now there is direct evidence of the consequences of our actions on a global scale. Now, more than ever, we need to act, we need to fix the damage we have wrought.
Stay safe and stay informed,