From advances in renewable power to the clear impacts of climate change, to denying the lot of it, climate and energy issues in 2013 are sometimes best expressed through graphs. Here are eight of the best from throughout the year:

Global Temperatures Keep Going Up

Temperature change over past 11,300 years (in blue, via Science, 2013) plus projected warming this century on humanity’s current emissions path (in red, via recent literature).
The chart above shows how dramatically temperatures have spiked in recent years, largely due to greenhouse gas pollution. The blue line shows global temperature levels over the last 11,300 years, and that spike right at the end shows what “temperature is changing 50 times faster than it did during the time modern civilization and agriculture developed” actually looks like. The red line is the best estimate scientists have for what the temperature is likely to be in the near future if we continue on our current trend. The more greenhouse gases are emitted, the more they trap heat within the atmosphere before it would ordinarily escape to space. That trapped heat is what is fueling much of the climate change in the modern era.
Carbon Dioxide Levels Hit 400ppm For The First Time In Recorded History
For the first time in recorded history, thanks to rampant burning of fossil fuels, CO2 levels in the atmosphere hit 400 parts per million in May 2013. “I wish it weren’t true but it looks like the world is going to blow through the 400 ppm level without losing a beat,” said Ralph Keeling, a geologist with the Scripps Institution of Oceanography which operates Hawaii’s Mauna Loa observatory. There has been an upward trajectory through the industrial era, as fossil fuel use has accelerated — this leads to catastrophic climate change.
Most Congressional Republicans Denied Climate Change
Denier Caucus[1]-02
While 2013 had plenty of climate horrors, perhaps most disappointing is how difficult it’s going to be to do something about it through congressional action. Fifty-six percent of House Republicans, 77 percent of the Republican members of the House Science Committee, and 90 percent of the Republican leadership in both houses deny that climate change is real and manmade.
The First Bulk Freighter Passed Through The Arctic, Carrying Coal
Plenty of smaller ships have made the trip through the Northwest Passage in the past, traveling from the west coast of North America, up around Alaska, and through the Arctic Circle for faster passage to Europe. But the Nordic Orion was the first bulk freighter to take advantage of the climate change-caused lack of sea ice to cut four days off its trip.
With the help of the sixth-lowest level of Arctic sea ice on record, the Nordic Orion left Vancouver, British Columbia for Finland with a load of coal, signaling a new era in shipping, brought to you by climate change.
Arctic Sea Ice Volume Still In Jeopardy
down escalator
NSIDC September Arctic sea ice extent (blue diamonds) with “recovery” years highlighted in red, vs. the long-term sea ice decline fit with a second order polynomial, also in red.
Between 1979 and 2012, Arctic sea ice volume collapsed, from 16,855 cubic kilometers to 3,261 cubic kilometers. In 2013, there was a 50 percent increase from the record low established in 2012. This collapse is several decades ahead of what climate models had once predicted.
The animated graph from Skeptical Science shows two different ways of looking at a trend. Climate deniers like to ignore the larger downward trend of the recorded data and seize upon every naturally varying uptick. Climate scientists see the broader curve pointing steadily downward. It would be great if there was no trend and the ice stayed stable, but that is not what the data shows.
The Price Of Solar Dropped Dramatically
This year saw the price of photovoltaic cells for solar panels continue its dramatic slide downward, reaching $0.74 per watt. That’s a 99 percent drop over the last 25 years, bringing solar to near-parity with the rest of the grid. Decades of support from state and federal governments in the U.S. and around the world in the form of R&D, purchases, renewable energy standards, and subsidies played a large role in making such a significant drop possible.
99 Percent of New Electric Capacity In October Came From Renewables
Though fossil fuel is still contributing a huge portion of electricity generation overall, October of 2013 was a great year for new capacity in renewables, most of it coming from solar. The only new fossil fuel capacity that month was five megawatts that came from oil.
Turns Out More Shale Gas Will Not Bring A Major Climate Benefit

More abundant, cheaper shale gas (dark blue) has little impact on annual growth in U.S. CO2 emissions through 2050 compared to low shale gas case (light blue). This is true for all six energy-economy models featured here. Deep cuts in CO2 require a rising carbon price (green).
Many people say that replacing natural gas with coal leads to smaller greenhouse gas emissions. Even ignoring methane leakage, it’s very possible that adding more natural gas could replace some combination of coal, renewables, nuclear power, and energy efficiency. Scientists took six energy-economy models to look at the CO2 emissions resulting from a high shale gas case and a low shale gas case.
“The high shale gas scenario is optimistic about both the ultimately recoverable resource base and recovery rates per well, which reduces natural gas production costs,” said Climate Progress’ Joe Romm. “Yet, averaging over all the models, these optimistic assumptions have little net impact on CO2 growth compared to the more pessimistic low shale gas case.”
What really makes for lower carbon emissions is a carbon price (as shown by the deep CO2 cuts in the green bars).