Kevin Trenberth in Science Magazine, August 2015:

The main pacemaker of variability in rates of GMST increase appears to be the PDO, with aerosols likely playing a role in the earlier big hiatus. There is speculation whether the latest El Niño event and a strong switch in the sign of the PDO since early 2014 (see the figure) mean that the GMST is stepping up again. The combination of decadal variability and a trend from increasing greenhouse gases makes the GMST record more like a rising staircase
than a monotonic rise. As greenhouse gas concentrations rise further, a negative decadal trend in GMST becomes less likely ( 13). But there will be fluctuations in rates of warming and big regional variations associated with natural variability. It is important to expect these and plan for them.


Paul Kantner now deceased at 74.

The newest Yale Video is looking like one of the more impactful in the series, given that it lays a two by four upside of one of denialdom’s most cherished myths, that satellite temperature data, or more specifically, satellite data since the 1998 El Nino event, are the one and only gold standard measure of whether the planet is gaining heat.

I’ve made a few cosmetic changes in the version above, added in an updated temperature graph to reflect that we now have finalized 2015 – and some, I hope, helpful graphics and animations to emphasize a few points of science-speak. (and I’ve uploaded to the Climate Denial Crock of the Week channel on YouTube, because so many of those subscribers, bless their hearts, still don’t know that I’m working with Yale for the last 4 years…)

One of the main points made by Andy Dessler, Carl Mears, and Ben Santer, is that temperature records of any kind would be suspect if they were not congruent with the actual behavior of biological and physical systems on the planet – many of which can be measured completely independently of one another – and so provide a useful check on each other.

The best example of this in the science literature is a famous 2008 paper from NASA’s Cynthia Rosenzweig and her team, in which more than 29,000 data sets of physical and biological processes are analyzed.


Observed impacts included changes to physical systems, such as glaciers shrinking, permafrost melting, and lakes and rivers warming. Biological systems also were impacted in a variety of ways, such as leaves unfolding and flowers blooming earlier in the spring, birds arriving earlier during migration periods, and plant and animal species moving toward Earth’s poles and higher in elevation. In aquatic environments such as oceans, lakes, and rivers, plankton and fish are shifting from cold-adapted to warm-adapted communities.

Read the rest of this entry »



In November, the International Energy Agency quietly dropped this bombshell projection: “Driven by continued policy support, renewables account for half of additional global generation, overtaking coal around 2030 to become the largest power source.”

The IEA notes, “With 60 cents of every dollar invested in new power plants to 2040 spent on renewable energy technologies, global renewables-based electricity generation increases by some 8,300 TeraWatt-hours (more than half of the increase in total generation).” That increase is “equivalent to the output of all of today’s fossil-fuel generation plants in China, the United States and the European Union combined.” It represents new investment of some $7 trillion in renewables over the next quarter century.

Significantly, this remarkable projection about the future of electricity is simply what the IEA believes is now going to happen given the pledges made in Paris by the world’s leading countries to rapidly expand renewable energy investment while restraining and, in many cases, reducing carbon pollution from fossil fuels through 2030. This is IEA’s “central scenario,” and in it the planet still warms 2.7°C by 2100 and more after that.

In short, this projection is not what would happen if the nations of world pursued the kind of aggressive policies they unanimously agreed to in Paris to avoid very dangerous warming and stay below total warming of 2°C. That would effectively end fossil fuel emissions by 2100.

Undereported story – Congress extended incentives for renewable energy.


Back in December, Congress did something it rarely does any more these days — struck a series of compromises and passed a bill, specifically a giant $1.8 trillion spending bill.

Among many other things, that bill extended the two key federal tax credits that support renewable energy: the production tax credit (PTC), which mostly goes to wind, and the investment tax credit (ITC), which goes to solar. Read the rest of this entry »


An interesting and tense moment at December’s American Geophysical Union conference came with an all star panel of climate scientists and energy experts, and clear lines were drawn between the “must have nuclear’ faction, lead by James Hansen, and the “renewables can do it” faction, represented by Mark Jacobson of Stanford – who I interviewed the same day – more on that soon.

New research seems to support Jacobson.


Analysts have long argued that nations aiming to use wind and solar power to curb emissions from fossil fuel burning would first have to invest heavily in new technologies to store electricity produced by these intermittent sources—after all, the sun isn’t always shining and the wind isn’t always blowing. But a study out today suggests that the United States could, at least in theory, use new high-voltage power lines to move renewable power across the nation, and essentially eliminate the need to add new storage capacity.

This improved national grid, based on existing technologies, could enable utilities to cut power-sector carbon dioxide emissions 80% from 1990 levels by 2030 without boosting power prices, researchers report today in Nature Climate Change.

The findings come on the heels of the Paris climate agreement, in which the United States pledged to cut its national emissions by up to 28% from 2005 levels by 2025. About 40% of U.S. emissions come from the power sector, and the U.S. Environmental Protection Agency (EPA) recently released rules that task states with reducing power-sector emissions. States can choose from a menu of strategies, EPA says, such as boosting renewable energy use.

But some observers wonder whether the U.S. power grid can rise to the renewables challenge. The grid is divided into several regional grids or “interconnections,” which contain smaller subdivisions. Because regions experience both sunless and windless periods, energy planners and experts have long believed that a wind- and solar-dominated grid would need to store some power for later use. The problem is that large-scale storage technologies haven’t been commercially realistic.

Alex MacDonald, a National Oceanic and Atmospheric Administration (NOAA) in Washington, D.C., researcher, was familiar with that problem. But he realized that researchers hadn’t explored all the potential solutions. For instance, meteorological data suggest that wind is always blowing somewhere in the United States, MacDonald says. So, although renewable energy output might be intermittent on a regional scale, it would have a more constant flow at a national scale. MacDonald wondered whether the U.S. grid might be able to overcome intermittency problems if it added high-voltage, direct-current (HVDC) transmission lines—which suffer less energy loss than do traditional alternating-current transmission lines—to connect regional grids, so that power could be moved to where it was needed.


The study also suggests the U.S. may make the transition without heavy investment in energy-storage technologies, which are seen by some as essential for helping to smooth out the intermittent flows from wind and solar farms.

Read the rest of this entry »

Part 3 from my interview with Dr Mears, whose work was prominently misused during the recent hearing chaired by Senator Ted Cruz.


California Atty. Gen. Kamala D. Harris is investigating whether Exxon Mobil Corp. repeatedly lied to the public and its shareholders about the risk to its business from climate change — and whether such actions could amount to securities fraud and violations of environmental laws.

Harris’ office is reviewing what Exxon Mobil knew about global warming and what the company told investors, a person close to the investigation said.

The move follows published reports, based on internal company documents, suggesting that during the 1980s and 1990s the company, then known as Exxon, used climate research as part of its planning and other business practices but simultaneously argued publicly that climate-change science was not clear cut.

(US Rep. Ted Lieu, US Rep – Torrance)  said he hopes the decision by Harris, representing a state with the eighth-largest economy in the world, will prompt other states and the Justice Department to investigate.

San Bernadino County Sun:

This is welcome news. California is investigating whether Exxon Mobil Corp. misled investors about the causes and effects of climate change and the likely impact on the oil company’s business.

It’s welcome not because Exxon Mobil necessarily did anything wrong or deserves punishment. That remains to be seen.

It’s welcome because the investigation by state Attorney General Kamala Harris can help to reveal exactly what Exxon Mobil knows — and has known over the years — about climate risks.

And knowing what companies like Exxon Mobil know could make for a more informed debate about the realities of global warming and what should be done to mitigate damage.

Official responses to climate change have mostly been based on data turned up by government, academic and environmental groups’ research.

Isn’t that data convincing? Not to many people, particularly political conservatives, who charge that the research is inconclusive or even that researchers have cooked the books in order to further arguments for stepped-up government regulation of business and fossil-fuels consumption.

Read the rest of this entry »

Above, my video about the effects of sea level rise in South Florida is the most popular entry in the “This is Not Cool” series from Yale Climate Connections.

The vid features an interview with Rolling Stone writer Jeff Goodell, who has been writing prolifically on climate change and sea level, and had just published a piece on the vulnerability of Miami to rising seas.

Anyway, heads up, I just talked to Jeff yesterday following his insightful play-by-play from the Paris Climate negotiations in November/December of last year.  I’ll be combining that interview with reactions from major scientific players that I was lucky enough to record just days after the Paris agreement was announced. That vid should be coming out next week, fingers crossed..

Meanwhile, on the campaign trail, a group of hard-pressed local officials from South Florida have been clamoring for Climate denying GOP candidates to at least acknowledge the sea water that is sloshing up around their collective ankles.  Good luck to them.

Miami Herald:

Marco Rubio and Jeb Bush have given little priority to climate change on the Republican presidential campaign trail, and a group of South Florida mayors have had enough.

Fifteen mayors from cities in Miami-Dade, Broward and Palm Beach counties wrote the two Miami candidates a letter asking them to meet with local leaders to “discuss the risks facing Florida communities due to climate change and help us chart a path forward to protect our state and the entire United States.”

“As mayors representing municipalities across Florida, we call on you to acknowledge the reality and urgency of climate change and to address the upcoming crisis it presents our communities,” both letters begin. “Our cities and towns are already coping with the impacts of climate change today. We will need leadership and concrete solutions from our next president.”

Most of the mayors are Democrats, and most of them serve in nonpartisan posts. But at least two are Republican, Tomás Regalado of Miami and Jim Cason of Coral Gables. Regalado is a Rubio supporter who showed up to the Florida senator’s fundraiser at the InterContinental Hotel downtown two weeks ago.

“We are in ground zero, and we need to have our candidates from Florida address the issue,” Regalado told the Miami Herald on Monday. “I understand that it’s a very delicate issue for them, because some of their constituents do not agree or understand.”

Read the rest of this entry »

We’re getting closer to the moment when Republican voters will choose which climate denier to run for the Presidency – and the best analysis I’ve seen of the process is this one from Stephen Colbert.