Carbon emissions from China could peak as soon as 2021, which is 9 years before the voluntary deadline in their Paris agreement pledge, a new peer-reviewed study finds.

Why it matters: China is by far the world's largest carbon emitter. The trajectory of its emissions affect whether the world has any chance of meeting the Paris temperature goals (or, more likely, how much they're overshot).

• It adds to separate analyses suggesting China could see a peak well before 2030 if things break right.

What they did: The paper in Nature Sustainability looks at China's urbanization trends and the emissions increases that come with it.

• They explore China's massive existing and developing cities and growing wealth through the lens of an environmental "Kuznets curve."
• It's the idea that per-capita emissions initially rise alongside per-capita GDP, but it's a bell-shaped curve in which higher incomes are eventually correlated with emissions decline.

What they found: China's cities and urban centers defy blanket characterization — they note a "great diversity in CO2 emissions and trends among individual cities." But in the aggregate...

"We project that China’s total emissions from fossil fuel and industrial processes will peak at 13–16GtCO2 at some point 5–10 yr ahead of 2030 on the basis of data from the 50 Chinese cities studied here over the period 2000–2016."

The intrigue: The paper says that policymakers will need to tailor policies to the characteristics of different cities and regions and their stage of development.

• For cities in economically advanced regions where industrial emissions may have already peaked or are close, that means more attention to lower-carbon lifestyles, efficient buildings, transport and renewables deployment.
• But for other areas seeing fast industrialization and urbanization, "efforts to constrain emissions should focus more on industrial sectors."
• In addition, it emphasizes the need to prevent "carbon leakage," whereby energy-intensive industries are just moved out the most developed cities.

Go deeper: China’s emissions ‘could peak 10 years earlier than Paris climate pledge’ (Carbon Brief)

2020 White House hopeful Sen. Kamala Harris and Rep. Alexandria Ocasio-Cortez floated legislation yesterday to ensure climate policy addresses the needs of the poor, people of color and other "frontline" communities.

Why it matters: The draft bill signals growing emphasis on the nexus between emissions-cutting proposals and broader social and racial justice goals.

• It's the most detail yet on climate from Harris, who backs the sweeping-but-vague Green New Deal, but whose campaign lacks a detailed climate platform thus far.
• The draft "Climate Equity Act" comes from her Senate office, but it's still a policy statement from a major White House candidate.

How it works: Environmental and climate bills would get a quantitative "equity score" akin to budgetary analyses conducted by the Congressional Budget Office.

• It also creates a process to measure costs and benefits of regulations on frontline communities, and aims to ensure federal investments benefit these populations.

The big picture: Harris said cutting emissions is not enough. "We must ensure that communities already contending with unsafe drinking water, toxic air, and lack of economic opportunity are not left behind," she said in a statement.

Quick take: Teaming up with AOC, the high-profile progressive with a big activist following, could help Harris politically as she competes for primary support on the left.

What's next: I'll be watching to see if Harris mentions the plan Wednesday night in this week's second CNN debate in Michigan, where the water crisis in Flint will surely surface.

Sen. Elizabeth Warren's new trade policy platform includes provisions that add to her collection of climate and energy proposals.

How it works: The wide-ranging plan (which Axios' Alayna Treene covered here) says new trade agreements would demand that partners...

• Eliminate fossil fuel subsidies.
• Have a national, independently verified plan consistent with the long-term Paris agreement goals.

Plus, for existing trade deals, Warren says she would renegotiate terms to meet her long list of preconditions.

Meanwhile, Warren also says she'd push for a multilateral agreement to protect domestic environmental policies, including preferential treatment for climate-friendly energy production, from possible World Trade Organization challenges.

Why it matters: Warren and several other candidates are emphasizing that domestic emissions-cutting goals are not enough.

• They're vowing to use diplomatic levers, international investment agencies and trade policy to promote low-carbon energy and climate policies abroad.

Speaking of climate policy, carbon pricing has lost some cachet on the left, but proposals from both parties are still proliferating on Capitol Hill, with several new bills surfacing lately.

Why it matters: None of them have any political traction now (the standard disclaimer!), but they provide some templates if that somehow changes in the coming years.

That brings me to the chart above, comparing projected carbon tax rates from various bill sponsors, courtesy of this helpful primer from Columbia University's Center on Global Energy Policy that examines recently released proposals.

The intrigue: Not only do the rates differ, but so do uses of the revenues.

• Some of them send the money directly back to the public.
• Others use it in different combinations for funding areas like infrastructure, general revenue, R&D and adaptation programs, and efforts to lower payroll taxes.

The oil-and-gas industry could realize $50 billion in cost-savings from wider deployment of drones over the next 5 years, a new Barclays report finds.

Why it matters: It's the sector that could see the greatest cost reductions over that period, as a "convergence" of tech developments — 5G, remote computing and AI — enable wider drone use in many industries.

What they found: The report explores a bunch of sectors, but sticking with oil-and-gas, Barclays' analysts see potential for major expansion in an industry already adopting drones for inspecting equipment and helping with exploration.

How it works: On the exploration side, that includes imaging, sampling, and "even 3D maps of potential sites to gather data prior to even deploying employees to these often remote and sometimes dangerous areas."

Congress: The Houston Chronicle looks at a massive and bipartisan new transportation legislation that's before the Senate's environment committee.

• "Republican and Democratic senators have agreed to pump billions of dollars in federal funding into building electric car charging stations and other infrastructure for low-emission vehicles," they report.
• While the measure also has provisions on protecting roads and bridges from climate-intensified disasters, it's all a "relatively small part of a $287 billion transportation bill," the paper reports.

Earnings: "A strong rise in oil and gas production helped BP offset weaker crude prices and refining profit to again beat profit expectations on Tuesday, boosting its shares," Reuters reports.

States: "[Colorado] State agencies and automobile manufacturers announced an agreement Monday on a proposal intended to get more electric vehicles on Colorado roads faster," the Denver Post reports.

"We do believe that Iran has the capability to meaningfully disrupt tanker traffic for Hormuz for a significant period of time — days to weeks. And we believe that this is much longer than what the market sees at the moment."

Who said it: Fernando Ferreira, an analyst with the Rapidan Energy Group, on the latest episode of the Platts Capitol Crude podcast.

Why it matters: The potential for disruption in the Strait of Hormuz — where roughly 19 million barrels of oil move per day — is getting lots of attention amid U.S.-Iran tensions.

The big picture: Rapidan's analysis explores several possibilities. One is a "7-day disruption scenario" that would cause Brent crude price to spike $15–$20 per barrel.

Listen to the whole thing