Under President Obama, especially in his second term, there's been a flurry of action on climate and energy. All sorts of new programs, rules, and regulations have rolled out, deals have been struck, and new commitments have been made on the international stage.

So it's a good time to pause for a moment, step back, and take stock.

How is the US doing on keeping its climate promises?

A new analysis from the Rhodium Group offers a nice high-level view. Let's walk through it.

America's current climate goals

In 2009, in the run-up to the Copenhagen climate talks, Obama committed the US to reducing its greenhouse emissions 17 percent below 2005 levels by 2020. (At the time, the White House also noted that he was "working closely with Congress to pass energy and climate legislation as soon as possible." Sigh.)

Then in 2014, as part of a bilateral climate agreement with China, Obama announced a new target: The US will cut its greenhouse gas emissions 26 to 28 percent below 2005 levels by 2025. Last year that target was submitted to the United Nations Framework Convention on Climate Change as America's official plan for emission reductions.

So those are the two targets on the books: 17 percent below 2005 by 2020, 26 to 28 percent below 2005 by 2025.

US emissions are already well below projections

What the Rhodium Group analysis sets out to do is make updated projections of US greenhouse gas emissions — projections that take into account the finalizing of the Clean Power Plan (CPP), the extension of the wind and solar tax credits, and other recent policy developments that aren't yet captured in the official forecasts from the Energy Information Administration (EIA).

But first, how's Obama doing so far?

Here's US emissions from 1990 to present:

Why the drop in emissions relative to the EIA's American Energy Outlook (AEO) forecast?

This has been the subject of much dispute. Here's what the Rhodium Group finds:

"Economic growth" refers to lower-than-expected growth, namely the recession Obama inherited.

"Carbon intensity" refers to the amount of carbon emitted by the energy sector per unit of energy consumed.

Carbon intensity declined thanks to "an unprecedented increase in the availability and use of natural gas from shale resources coupled with expanded renewable power generation thanks to the federal Production Tax Credit (PTC) and Investment Tax Credit (ITC), state Renewable Portfolio Standards (RPS), other federal and state policies, and a decline in renewable technology costs."

"Energy intensity" has to do with how much GDP the US economy produces per ton of carbon dioxide it emits.

Energy intensity has been declining thanks to "federal and state efficiency programs, fuel economy standards for light-duty vehicles (and high oil prices), building codes, technological improvements and shifts in the structure of the US economy."

All three of these categories — economic growth, carbon intensity, and energy intensity — are sources of considerable uncertainty in projecting emissions out through 2025.

If economic growth picks up, it could raise emissions. If technology costs fall faster than expected, it could lower them. If energy efficiency grows faster than expected, it could lower them. And so on.

Taking all those uncertainties into account, the Rhodium Group analysts have generated a provisional forecast out to 2025. The news is not great.

Current US climate policies will not achieve current US climate goals

First the analysts did a projection based on all current US policies on the books, including the CPP, the ITC, the PTC, the RPSs, and various other acronyms.

(As I noted yesterday, there is much uncertainty around how various states will implement the CPP. The analysts make some simplifying assumptions about that; see the paper for details.)

Anyway, here's what they come up with:

The CPP and the tax extenders together begin pushing emissions on a downward trajectory, but not enough to hit either US target.

But remember, there are all sorts of uncertainties involved in these projections.

Here's a graph that takes two sources of uncertainty into account: LULUCF (land use, land use change, and forests) uncertainty, which has to do with how much carbon US carbon sinks will absorb, and economic and technology uncertainty, which has to do with economic growth, transportation demand, the cost of renewable energy.

Here's a projection with those uncertainties represented:

As you can see, with current policies if the US gets some lucky breaks (good forest management, cheap renewable energy) or some, uh, unlucky breaks (lower-than-expected economic growth) it could conceivably hit its 2020 target.

But no scenario gets to the 2025 target with current policies. The authors conclude:

... current policies are not sufficient to meet US climate targets except under the most optimistic assumptions. Even then only the 2020 target may be achievable. In 2025 a considerable gap remains.

Policies currently in the pipeline brighten the picture somewhat

Several policies developed under Obama are still being finalized or only partially implemented. The analysts have a go at including those in a projection as well.

They include:

Methane rules, both on landfills and on oil and gas operations

Reductions in hydrofluorocarbons (HFCs), both through EPA rules and through the newly reinvigorated Montreal Protocol

Transportation rules, mainly fuel economy standards. In coming years there will be a midterm evaluation of whether light-duty standards should be further raised, as well as decisions on phase 2 standards for medium- and heavy-duty vehicles (delivery trucks, big rigs, etc.).

Within each of these categories, there's uncertainty about how stringent rules will be and how soon their benefits will manifest. So the analysts added a third uncertainty spread, "proposed policy uncertainty," to their projection:

The proposed policies are ... somewhat helpful. But only a little.

Here are the spreads in the projections, given the uncertainties:

Given everything Obama has done and is currently working on doing, if everything goes right, the US will barely hit its 2020 target.

But it will take more to hit the 2025 target pledged in Paris.

Policies that could get the US further, if and only if...

The authors suggest a few avenues for further action.

The feds can support R&D to drive down technology costs, encourage ride-sharing and public transportation to reduce VMT, make sure the CPP is implemented in a rigorous and sensible way, raise fuel economy standards, reform public land leasing, and encourage state and local efforts at carbon reduction.

Beyond that, there are probably ways for a president to make even more aggressive use of the Clean Air Act. And there are various other incremental steps EPA can take based on existing rules.

Here's the thing, though: Any policy that requires legislative action is unlikely to happen on a timescale necessary to produce real effects by 2025 — not as long as Republicans hold the House, which they are expected to through 2020 at least.

New policies that might have a real effect on US greenhouse gas emissions in 2025 are likely to come almost exclusively from the executive branch.

That will make it extremely difficult to hit the target Obama promised in Paris. There are, in the end, limits to what the president can do.

And even that chance only exists if a Democrat is elected president in 2016, and probably 2020 as well. All the current Republican candidates have pledged to roll back Obama's climate rules and ramp up support for fossil fuels; they will find eager partners in a Republican Congress.

An aggressive Democrat in the Oval Office is a necessary condition of success in meeting the Paris target, but it is not a sufficient condition. Many new policies are needed, and many exogenous developments will need to play out just right.

It's a narrow path, with considerable US credibility at stake.