Monday's award of the last of the 2018 Nobels took place less than a month after the 10th anniversary of the collapse of investment bank Lehman Brothers.
The Royal Academy of Sciences on Monday awarded Nobel Prizes in Economic Sciences to two American university professors.
Nordhaus' research focuses on global carbon taxes to offset greenhouse gas emissions.
Romer, who is at the NYU Stern School of Business in NY, was honoured for his work on the role of technological change in economic growth.
"We are actually going backwards in the United States with the disastrous policies of the Trump administration", the 77-year-old added. The statement said Nordhaus was the first person to create a quantitative model that describes the global interplay between the economy and the climate.
Romer is a professor at NYU whose theory models how macroeconomics. affects companies' willingness and ability to come up with new ideas.
The committee said: "Romer demonstrates how knowledge can function as a driver of long-term economic growth".
"Many people think that dealing with protecting the environment will be so costly and so hard that they just want to ignore the problem".
"I hope the prize will help people see humans are capable of wonderful accomplishments when we try to do something".
It said time was running out to avert disaster, noting that our planet's surface has already warmed one degree Celsius (1.8 degrees Fahrenheit).
The economics prize wraps up the 2018 Nobel awards season, notable this year for the lack of a literature prize, postponed for the first time in 70 years over a rape scandal that came to light as part of the #MeToo movement.
Many economists have since endorsed the concept of taxing carbon and using this financial lever to influence societal behavior. What other ways do you feel like the global community can work together to solve climate change?
"His tools allow us to simulate how the economy and climate would co-evolve in the future under alternative assumptions about the workings of nature and the market economy, including relevant policies".
Last year's win by American Richard Thaler was unusually accessible to the layman - his work studied the human irrationality that can mess with economic theory.
U.S. President Donald Trump has repeatedly called climate change a hoax, and a year ago announced that he would withdraw the United States from a global pact to combat it reached in 2015, calling the deal's demands for emissions cuts too costly.
The peace prize, which was announced in Oslo on October 5, was awarded to Denis Mukwege, a gynecologist from the Democratic Republic of Congo, and Nadia Murad, an activist and victim of war crimes.