Joe Biden unveiled a wide-ranging climate and energy platform for his 2020 campaign Tuesday, vowing to go "well beyond" President Obama's policies at a time when he's facing skepticism on the left.

The big picture: It calls for achieving net-zero U.S. greenhouse gas emissions no later than 2050. That top-level goal is within range of Jay Inslee's detailed plan, which calls for net-zero "as fast as possible" and by 2045 at the latest.

Why it matters: Biden is the early Democratic frontrunner and the stakes are high as President Trump unwinds existing policies.

The proposal follows dire scientific warnings in recent years about immense harm if the world fails to steeply cut emissions that are still rising.

Yes, but: Several key portions would require legislation. That's a big lift unless Democrats regain the Senate and ease filibuster rules or use special budget-related legislation that could allow provisions to pass with a simple majority.

On the legislative front, Biden calls for a bill that creates "legally binding" emissions cuts with an "enforcement mechanism" to achieve the 2050 goal.

It says "polluters must bear the full cost of the carbon pollution," and the campaign confirmed to Axios this would include a price on carbon.

It calls for big spending increases in low-carbon energy and "resilient infrastructure" funded by reversing the Trump administration's 2017 corporate tax cuts.

It proposes a suite of tax code changes. They range from expanded electric vehicle credits for low-carbon manufacturing to ending fossil fuel-related incentives.

When it comes to executive actions, the proposal vows steps such as:

"Aggressive" methane limits for the oil-and-gas sector.

"Rigorous" new vehicle economy standards aimed at ultimately ensuring 100% of light- and medium-duty sales are electric vehicles, although no date is provided.

Tougher appliance and building efficiency standards.

Several social justice and equity provisions, such as stepped up enforcement of pollution that affects communities of color and the poor.

Various steps to help fossil fuel workers "impacted by the climate transformation."

On the international front, Biden is vowing to go further than keeping the U.S. in the Paris climate deal. It calls for:

A "major diplomatic push" to have other nations increase their emissions-cutting ambition.

New policies to weave climate into trade policy, along with get-tough language on China.

"Carbon adjustment fees or quotas on carbon-intensive goods" from countries that are "failing to meet" their climate obligations.

Between the lines: Biden's platform praises the Green New Deal, calling it a "crucial framework."

But it stops short of flatly endorsing the formal Capitol Hill GND resolution led by Rep. Alexandria Ocasio-Cortez that has attracted criticism from some labor officials — a key Biden constituency.

It's not clear whether the plan is enough to stem attacks from activists who were angered in early May when a Biden adviser suggested he would take a "middle ground" approach.

The campaign tells Axios that Biden will sign the activist-backed "no fossil fuel money" pledge on contributions that many other candidates have already signed.

It also has another nod to the left with a call for "banning new oil and gas permitting on public lands and waters."

By the numbers: Some of the top-line figures and goals in the plan include:

$1.7 trillion in federal investments over 10 years, including $400 billion in "clean energy research and innovation."

A goal of "conserving 30% of America's lands and waters by 2030."

A target of cutting the CO2 emissions from the U.S. building stock by 50% by 2035.

Deployment of 500,000 public EV charging stations by 2030.

Quick take, via Axios Science editor Andrew Freedman: The goals are generally in line with what the UN says is needed globally to meet the most stringent Paris target of 1.5 degrees Celsius of warming compared to pre-industrial levels, which would be net zero global emissions by 2050.

However, for that to happen worldwide, the U.S. presumably would have to get there much faster.

Go deeper: Climate change is a massive issue for Democrats in 2020