The study, Energy investments under climate policy: A comparison of global models, published in the journal Climate Change Economics (DOI: 10.1142/S2010007813400101 | 2013) explored global energy spending and concluded that low-carbon energy and energy efficiency investments of about 1.1 trillion annually are required, to meet the emissions reduction targets to keep the world below 2°C.

In context, additional $0.8 trillion are needed, when taking the current clean energy investments into account, which are about $200 billion a year.

However, governments worldwide spending $523 billion each year on fossil energies, thus moving subsidies to cleaner investments, would help to close the current investment gap for clean-tech. Once met the world has a 70 percent chance of keeping temperatures below 2°C.

NewScientist interviewed the study author, McCollum:”The magnitude of the clean-energy investment challenge is roughly similar to today’s fossil-fuel subsidies. So if we used the subsidies for coal, oil and natural gas to invest in solar, wind and nuclear energy, global warming would be close to being solved.”

The scientist also cautioned:

“What is inescapable is that time is short, because most energy infrastructure has a lifetime of 30 to 60 years. Unless the [clean energy investment] gap is filled rather quickly, the 2°C target could potentially become out of reach.”

However, at the Breakthrough Forum 2014, David Spratt, a climate expert from Climate Code Red argued that there is a high likelihood that there is no carbon budget left (the amount of emissions civilization can emit to stay below a 2°C target). Further he argues that the 2°C is not a safe target, which is in line with the conclusions of many climate experts and climate scientists.

David Spratt, points out the following problems with the 2°C target:

• Boundary between dangerous and very dangerous
• 1°C warmer than human civilisation has ever experienced
• Tipping points (e.g. Arctic sea ice, West Antarctica) have already been passed at just 0.8°C of warming.
• West Antarctica a game changer, one of many surprises.
• Other irreversible tipping points likely at less than 2°C.
• Sea-level rise likely in tens of metres
• Many ecosystem lost (e.g. Arctic, corals)
• Nations disappear and mass loss of human life

Listen to David Spratt’s presentation, or read it.
https://player.vimeo.com/video/99804725?color=e01469

Related
Obama Administration Announces Massive Climate Change Funding