In recent years, New Yorkers, like people all over the world, have faced the realities of human-made climate change: extreme storms, rising sea levels, summer heat waves, massive winter nor’easters, and a $20 billion plan to reduce future flooding. Last year, the United States as a whole experienced the highest losses from climate disasters, an estimated $309 billion.
 
With the Big Oil lobby firmly entrenched in the Trump administration, national action against climate change has ground to a halt. The path to climate safety is closing fast.
 
Climate change results overwhelmingly from the burning of coal, oil and gas, and the carbon dioxide emissions that result. (Emissions from agricultural production and land use change are also  drivers.) The key to climate safety is therefore decarbonization: to shift from the fossil fuels to zero-carbon energy, such as wind, solar, hydro and nuclear power.
 
The future of the planet therefore depends mainly on the few places that produce the preponderance of fossil fuels: the U.S. and Canada, the European Union, China, India, Russia and the countries of the Arabian Gulf.
 
In each of these countries, the political pitched battle is between the 20th-century giants, Big Oil and Big Coal and the 21st-century realities for zero-carbon energy. The fossil-fuel industry, and the politicians on their pay, work overtime to maintain our addiction to oil and gas guzzlers. Their playbook is that of Big Tobacco, which has fought for decades to maintain the mass addiction to cigarettes.
 
Big Tobacco was responsible for stoking a cancer pandemic; Big Oil threatens life itself, by runaway global warming and its dire consequences.
 
Both cigarettes and fossil fuels are slow-acting killers. They catch up with us gradually. They invite a lot of denial by the individuals using them and opportunities to sow confusion by the marketers pushing them. They are both addictive in their way. They are produced by powerful companies with friends in high places.
 
Yet in many ways, fossil fuels are even trickier to confront, because it has long seemed that our very lives and prosperity depend on the continued use of these sources of energy. The challenge is global, not local or national. Who can do without driving, flying, home heating or electricity?
 
Indeed, from the first warnings about global warming at least 30 years ago, we have gone from year to year, decade to decade, with no coherent national or global plan of action.
 
Because of decades of delay, we are now up again the abyss (a fact repeatedly obscured or denied by Big Oil, but true nonetheless).
 
Here are the scientific basics. Global warming depends on the amount of CO2 in the atmosphere (measured as parts CO2 per million molecules of atmosphere). The more CO2, the higher the Earth’s temperature.
 
Since the start of industrialization (around 1750), CO2 levels have risen from around 280 parts per million to 407 parts per million in 2017. In 2017, the Earth’s average temperature was 1.17 degrees Centigrade, or 2.1 degrees Fahrenheit, above the estimated pre-industrial average temperature.
 
Both CO2 and temperature are continuing to rise, and with that, so do the dire risks of extreme storms, heat waves, floods, rising sea levels, forest fires and other catastrophes.
 
The food supply is at risk, as crops are of course highly sensitive to temperatures, rainfall and other climate conditions.
 
The oceans are at dire risk too, since some of the CO2 in the atmospheric CO2 dissolves in the ocean, and creates the same kind of acidity (carbonic acid) as a soda, with disastrous effect on marine life.
 
The path to climate safety is turning off, step by step, the human-made emissions of CO2 into the atmosphere, mainly by turning off the burning of coal, oil and gas.
 
One possible alternative is called carbon capture and storage, meaning that we would capture the CO2 from the use of fossil fuels and pump the CO2 underground. That would be a hugely expensive and contentious operation, and so is not likely to play a decisive role.
 
Ending the addiction to coal, oil and gas is our best and low-cost option.
 
But how much time do we have? The scientists have long warned us to stay below 2-degrees C (3.6-degrees F) warming, and we are far more than halfway there. Our greatest scientists have told us that even 2-degrees C warming would be recklessly high for humanity.
 
My Columbia University colleague Dr. James Hansen, for 30 years NASA’s leading climate scientist, warns us that even with warming well below 2-degree C, human-induced warming could lead to the disintegration of parts of the ice sheets of Antarctica and Greenland, causing the sea level to rise by as much as 6-9 meters.
 
Indeed, the last time that Earth was as warm as now, or just slightly warmer, (roughly 120,000 years ago, in a geologic period called the Eemian), the sea level was roughly 6-9 meters higher than now. That’s not good news for us who live on small islands, such as Manhattan.
 
The key goal is to limit warming to “well below 2-degree C warming,” a global commitment embraced by all the world’s nations in the 2015 Paris Climate Agreement, signed by President Barack Obama and other world leaders.
 
That, of course, is the global agreement that Trump has promised to abandon.
 
Yet we make a huge mistake if we think Trump is alone in this plan to abandon climate safety. Think of Big Oil paying the campaign bills of the Republic Party leadership in Congress. Twenty-two Republican senators, under the influence of Big Oil, wrote to Trump to urge him to pull out of Paris and play by the rules of Big Oil, not the rules of human survival.
 
Could we find a way to hold the line at a 2-degree C upper limit on warming?
 
The answer is a decisive yes, but it requires clear and ambitions targets and policies to usher in a zero-carbon energy system. Climate science gives us the basic framework: We need to end our dependency on fossil fuels by 2050. By mid-century, we need a world energy system based on zero-carbon energy.
 
Remarkable as it sounds, this is actually feasible at low cost, and with a major side benefit: much less air and water pollution as well.
 
The think tank that I direct on behalf of UN Secretary-General Antonio Guterres, the UN Sustainable Development Solutions Network, recently issued a detailed report on how to decarbonize the energy system of the U.S. Northeast, including, of course, New York City.
 
The findings are fascinating. By mid-century, the Northeast could operate overwhelmingly on zero-carbon energy by teaming up with Canada to link U.S. wind and solar energy with Canada’s hydroelectric power.
 
Power would flow across the border in both directions, depending on the season. And Canada’s hydroelectric reservoirs would act as giant batteries for the linked U.S.-Canada grid. When the wind and solar power are in excess in the United States, water would be stored in Canada’s reservoirs to produce hydropower during periods of lower wind and solar energy.
 
Utilizing this clean electricity, the rest of the regional economy could be made all-electric and zero-emitting.
 
Cars and public transport would be electric, a direction in which they are already moving.  The heating of buildings would also be electric. Planes and large ships would shift to synthetic liquid fuels also produced with renewable energy.
 
The costs of moving to a low-carbon energy system (based on wind, solar and other low-carbon power; electric vehicles; heat pumps for buildings; smart grids and efficient appliances; and so on) are falling very rapidly, and would most likely be less than 1% of income.
 
The gains, meanwhile, would save the planet.
 
The Northeast United States is of course not alone in America’s huge potential for developing low-cost clean energy. The Western states have vast solar energy potential, including from Mexico. The Midwest has vast wind power. And so on.
 
The best, low-cost solution is a U.S.-Canada-Mexico power grid building on the enormous zero-carbon energy resources of North America.
 
The bottom line for people who care about the climate and the planet is this: Don’t be dispirited, not even with Republicans running Congress and Trump in the White House. We can fix this problem if we try.
 
And there’s global momentum, too.
 
I recently attended an important conference in Beijing, China, where the Chinese government brought representatives from dozens of countries from around the world to design a global-scale solution like the one I’ve described for the U.S.
 
China’s impressive proposal, called Global Energy Interconnection, would link up the world’s high-quality zero-carbon energy, including wind, solar, hydro, nuclear and others sources, into a large-interconnected global transmission system. Clean, interconnected energy and the electrification of vehicles, buildings and industry, would be the basis for a rapid worldwide shift from fossil fuels to zero-carbon energy.
 
Despite the years of inaction, and the rising and real threats of climate catastrophe, there is actually reason for hope.
 
We now know the path to climate safety: shifting from fossil fuels to zero-carbon energy by mid-century. We now know the main technologies that can get us there at low cost: zero-carbon electricity; electrification of vehicles, buildings, and industry; and energy efficiency with smart grids and smart appliances.
 
We even have a roadmap within the U.S. and at the global scale.
 
Yes, the future struggles to be born. The oil lobby continues to spread the campaign dollars. Even Canada’s Prime Minister Justin Trudeau, an environmental leader, backs yet another oil pipeline in order to maintain political support in oil-rich Alberta. The result is a narrow vested interest pitted against the needs of humanity.
 
But we’ll get there if people keep pressing.
 
New York City has found a creative way to help break the political hammerlock. This January, the City announced it would take Big Oil to court. If New Yorkers are to pay $20 billion or more to keep the city safe from rising sea levels and floods, let the oil industry pick up the tab for the “public nuisance” it has knowingly and willfully created. It’s an excellent idea, and one that a judge may well accept. Similar lawsuits are now sprouting up around the country and the world.
 
In the end, I remain confident that the needs of humanity will prevail against the narrow interests of a few short-sighted wealth holders.
 
Happy Earth Day 2018, and many more.
 
Sachs is University Professor at Columbia University and director of the UN Sustainable Development Solutions Network.

http://www.nydailynews.com/opinion/fix-climate-change-article-1.3946307