The science is clear: climate change is real and the world must act to mitigate its impacts and keep global temperatures within a safe limit.

The causes of climate change and the greenhouse effect

Climate change is caused by both the loss of our earth’s natural carbon sinks (such as forests that absorb carbon) and the increase of greenhouse gases in the atmosphere (produced through the burning of fossil fuels).

The earth is kept at a habitable temperature through a natural process called the greenhouse effect, in which certain greenhouse gases trap heat within the atmosphere by absorbing thermal infrared radiation and redirecting it towards the surface. Normally, this process traps enough heat in our atmosphere to keep our planet at a temperature that can support life.

But human activity is changing the composition of our skies by releasing high quantities of greenhouse gases such as carbon dioxide, methane and nitrous oxide in to the atmosphere. We do this through activities which include cutting down and burning forests and burning fossil fuels.

Scientific consensus

The Intergovernmental Panel on Climate Change (IPCC) is an international group of climate scientists who provide recommendations that enable governments to make informed policy decisions. Through the work of the IPCC, consensus has been reached that:

  • Climate change is real
  • The concentration of greenhouse gases in our atmosphere is rising rapidly
  • Global average temperatures are rising and have increased about 1oC from pre-industrial levels 1
  • Human actions are influencing the climate

The IPCC has also provided data which shows we need to keep our global temperature within a ‘safe’ limit of below 2oC – the maximum average temperature increase that governments believe we can afford to ‘adapt’ to. Learn more about the 2oC threshold and how global governments have committed to keeping the climate within these limits through the Paris Agreement.

The carbon budget

How much more carbon can we emit before we lock in dangerous levels of climate change? And how much carbon can we have in the atmosphere before we are no longer able to keep temperature rise to below 2oC, as agreed globally?

Enter the global carbon budget. Just like a financial budget, this tells us how much carbon we have left to ‘spend’ before we run out.

Science tells us that if we want to stay below 2oC, the carbon budget is reached once we emit another 805 gigatonnes of carbon dioxide (GtCO2e). If we want to stay below 1.5oC, the aspirational target of the global climate agreement, we have even less leeway: 205 GtCO22, 3. But this only gives us a 66% chance of limiting the temperature increase to 2oC or 1.5oC respectively.

We’ve already used up our budget for a 100% chance of limiting warming to 1.5oC4. And at current emissions levels, we only have 5 years left to have even a 66% chance of keeping climate change below 1.5oC.

We have more time for 2oC but we must change course quickly; every increase in temperature brings with it more uncertainty and more financial, ecological, and human costs.

The role of forests

Forests are a natural climate solution, acting as carbon sponges to absorb the CO2 that we all produce; with the added co-benefits of supporting ecosystems, protecting habitats and offering impoverished communities a more sustainable way of making a living. Keeping our forests standing is a critical and cost-effective climate solution.

Photosynthesis is the process by which plants absorb carbon to produce the energy they need to grow and breathe oxygen back out into the world – so when trees are cut down or burned it gets released back to the atmosphere. Halting deforestation could contribute about one-third of the carbon emissions required to keep our climate safe.

A recent study by The Nature Conservancy published in PNAS showed that natural climate solutions including avoiding deforestation can actually deliver a huge 37% of the emissions reductions needed to achieve our Paris Agreement goals.

At Ecosphere+ we know that urgent action is required to reduce emissions. That is why our projects work to address the causes of deforestation by working with local people to protect threatened forests.

If you want to know more about your carbon footprint and how you can rebalance it visit our carbon calculator or you can contact us for more information.

[1] NASA’s Goddard Institute for Space Studies (GISS)

[2] 66% chance of staying under the respective temperatures

[3] Carbon Brief (2016) ‘Analysis: Only five years left before 1.5C carbon budget is blown. Found at: https://www.carbonbrief.org/analysis-only-five-years-left-before-one-point-five-c-budget-is-blown

[4] Carbon Tracker 2016