Democratic 2020 presidential candidate Beto O'Rourke speaks during a campaign stop at The Beancounter Coffeehouse & Drinkery in Burlington, Iowa, U.S. March 14, 2019.

Democratic presidential candidate Beto O'Rourke on Monday revealed a $5 trillion plan to address climate change that would be funded largely by changes to the tax code.

The former U.S. congressman from Texas is pitching a 10-year plan that seeks to spur investment in clean technology and energy efficiency, achieve net-zero greenhouse gas emissions by 2050 and shore up communities vulnerable to the effects of climate change.

"The greatest threat we face — which will test our country, our democracy, every single one of us — is climate change," O'Rourke said in a statement. "We have one last chance to unleash the ingenuity and political will of hundreds of millions of Americans to meet this moment before it's too late."

O'Rourke is the latest Democrat to introduce an overarching framework for combating climate change. The world's top climate scientists say the nations of the world must take "unprecedented" and immediate action to prevent catastrophic impact from global warming in the coming years.

Parts of O'Rourke's proposal dovetail with Rep. Alexandria Ocasio-Cortez's Green New Deal, but O'Rourke's proposal is fundamentally different because it seeks to leverage an initial government investment in order to spark private spending. Under Ocasio-Cortez's plan, the U.S. government would entirely fund a radical transformation of the nation's energy, transportation and building sectors over the course of a decade.

O'Rourke said the first bill he would send to Congress as president would include a $1.5 trillion investment in infrastructure, innovation and communities. The bill would make structural changes to the tax code that "ensure corporations and the wealthiest among us pay their fair share" and end billions of dollars in tax breaks to fossil fuel companies.

The bill would include $600 billion, split evenly between tax credits and direct investments in infrastructure. O'Rourke said that will mobilize at least $4 trillion in additional capital spending.

The campaign believes that will break down to about $1 trillion in spending to accelerate the development of new energy efficiency and alternative power technologies that slash emissions. It says another $3 trillion in spending would be underpinned by institutions like the Rural Utility Service and a new finance authority.

O'Rourke's bill would also allocate $250 billion to encourage private investment in research and development and climate science. An additional $650 billion investment aims to spur $1.2 trillion in grants for housing, transportation, public health, job training and other benefits for Americans "on the front-lines of a changing climate and those disrupted by the forces of an economy in transition."

The candidate also says he would sign a number of executive orders on his first day in office, including to reenter the Paris climate agreement. President Donald Trump, who questions climate science and downplays its impacts, withdrew the U.S. from the global framework for reducing emissions.

As president, O'Rourke said, he would develop a legally enforceable standard to make sure that by 2050 the U.S. achieves net zero emissions, meaning the nation offsets any greenhouse gas emissions with measures to offset an equal amount.

O'Rourke also said he would take several measures to help communities deal with and recover from fires, floods, droughts and hurricanes linked to climate change. Those include increasing spending on mitigation projects before climate disasters strike and amending the law to make sure communities hit by these weather events are built back stronger.