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The key to the climate change challenge is in discovering how to accommodate the energy and material requirements of the human population while reducing the environmental impact of civilization’s needs. The challenge lies in finding pathways to achieve this goal while stabilizing the climate and protecting Earth’s critical life support systems – all for generations to come. This is a significant challenge, but there are many exciting solutions emerging every day!

Explore AGCI’s Energy Table and its ‘Getting Near Zero’ interactive companion tool to explore current and alternative global energy scenarios. The global energy system is incredibly complex. These tools distill energy data from hundreds of leading sources into interactive formats. Enjoy!


The Past. Climate-Energy-Carbon Nexus

The benefits of access to energy over the course of the Industrial Age do not have to stay tightly coupled with fossil fuel emissions. Energy solutions tackle this historical linkage between available energy and emissions. How to achieve the decoupling of, while rectifying, the problem that some of the world’s population do not have adequate access to the basic services energy provides is at the core of the climate­-energy-­carbon nexus.

Figure 1. Gigajoules per capita and tons CO2 per person annually. Since 1965 the population of the Earth has more than doubled from 3.3 billion to over 7 billion today. During these years, global energy consumption has more than tripled. Figure from Our Finite World

Figure 1 shows that globally energy and CO2 emissions per capita have both gone up since the mid 1960s. Presently about 80% of the total primary energy of the world comes from fossil sources which in turn drive global emissions of CO2.

Conventional wisdom once assumed that greater energy use leads to greater greenhouse gas emissions, and a higher standard of living and overall wellbeing require greater energy use per capita. In many ways these two notions have been represented in the unfolding of the Industrial Age and the energy provided by fossil fuels, but they do not have to hold true as we move forward. Greenhouse gas emissions can be decoupled from wealth, wellbeing, and energy — a grand challenge for the 21st century.

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The Present. The Grand Challenge — Stabilizing the Climate

Having a better than even chance of stabilizing the climate at less than a 2 degree Celsius (3.6 deg Fahrenheit) rise over preindustrial global temperatures will require annual emissions peaking in the near future and thereafter gradually declining to near zero.

In 1992 the nations of the world got together in Rio de Janeiro for the UN organized Earth Summit. At the summit, the UN Framework Convention on Climate Change (UNFCCC) was signed. It is the international treaty specifically addressing concerns over humankind’s ability to alter the Earth’s Climate. 196 nations ratified the treaty to “stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.”

At a Conference of the Parties (COP) of the UNFCCC at Cancun, Mexico in 2010, a 2 degree Celsius (3.6 degree Fahrenheit) limit was included as part of the Cancun Agreements. Climate change is more than just temperature change. Change that is “dangerous” in the interconnected complexity of Earth and the biosphere is not as simple as just looking at a temperature limit, but it is a straightforward measurable goal that nations can work toward for the upcoming next COP (COP21) in Paris 2015.

Climate models offer a tool for assessing what needs to happen in emissions reductions to have a fair chance of achieving the 2 C degree goal. The figure below shows historical global temperatures starting in 1850 to the present and climate model projections out to 2300 depending on a high (red) and low (blue) emissions path. The blue path requires aggressive emission reductions ­ less of a gradual transition in the energy system – to one more like an energy revolution.

Figure 1. From Meinshausen et al 2011 in Climatic Change. Since 1990, the Intergovernmental Panel on Climate Change (IPCC) has used climate models to project future climate change based on socioeconomic scenarios. Two of the present set of scenarios are represented in this figure. A high emissions scenario (RCP 8.5 the red curve) and a low emissions scenario (RCP 2.6 the blue curve). The RCP 2.6 has a better than even chance of keeping the earth below a 2 degree C increase over the pre-­industrial global average surface temperature.
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The Future. Energy and Technology Pathways

Transitioning from an energy system dependent on fossil energy will require an energy revolution if the world is to achieve the UN goal of a 2 degree C limit. Energy expert Vaclav Smil notes that past energy transitions take multiple decades to achieve. Accelerating the business as usual timeline for transition will take a focused effort and considerable political will.

In the figure below note that as of 2012, all sources of energy use were on the rise except for nuclear, with coal showing the steepest rise since 2000. It’s also important to note that past trends while carrying tremendous inertia do not necessarily continue. Exponential rates of change such as in the solar and wind markets, if sustained, have short doubling times. Policies can have a dramatic impact on realized emissions by instituting performance standards. National or state goals are being set altering the rate of renewable energy sources being deployed. Recent examples include Germany and California working toward longterm goals for carbon emission reduction more in step with the required reductions required to stabilize the climate.

Figure 1. World Energy Consumption, BP Statistical Review of World Energy 2014. Aside from a slight dip during the global recession beginning in 2008, total energy supply has increased from 1971 to 2012. About 82% of the energy supply was fossil based, with biomass/fuel, nuclear, hydro, wind and solar making up the balance. Explore the Data

Solutions can be grouped into 4 general areas;

1) Improvements in efficiency & whole systems design (see Figure 2 below),
2) Behavioral change and consumer choice,
3) Advances in and deployment of clean technologies,
4) Policies that drive change. - Learn about Policies that Work from our partners at Energy Innovation.

Figure 2 - Whole Systems Design - illustrating a cradle to cradle model of manufacturing and consumption. "Biological and technical nutrients (C2C)" by Zhiying.lim - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons

From a carbon emissions standpoint the key factors are population, economic growth, the carbon intensity of energy use, and the energy intensity of the economy. These factors are know as the Kaya Identity. For a hands on activity to gain a sense of how these factors interact to produce annual global emissions of CO2, try this sample problem.

Sample Problem

Along with advances in technology and adoption of existing clean energy options, education is paramount. An educated citizenry on topics like climate & energy literacy has the ability to make informed energy choices and consider those choices in relation to their understanding of how the Earth’s climate is changing as a result of human activity. Improved education on these topics requires effective Climate Communication.

Along with advances in technology and adoption of existing clean energy options, education is paramount. An educated citizenry on topics like climate & energy literacy has the ability to make informed energy choices and consider those choices in relation to their understanding of how the Earth’s climate is changing as a result of human activity.

To this end, we post quarterly Scientific Summaries, which review and synthesize articles on some of the latest advances in climate and energy policy, technology, and scientific breakthroughs. We publish a public archive of these quarterly reports as an educational resource.

Improved education on these topics also requires effective communication. We proudly partner with Susan Hassol's Climate Communication, which provides training for scientists on how to be reach out and communicate more effectively with the public; along with Hal Harvey's Energy Innovation which educates decision makers around the world on urban sustainability, power sector transformation, and energy policy solutions.

More Solution Ideas Quarterly Supplements