SPECIAL REPORT-The Reuters Hot List: the world's top climate scientists

In 1988, U.S. scientist James Hansen went before Congress and testified about his research into the warming of the planet. More than 30 years later, Hansen's prediction that the average global temperature could rise by about 1 degree Celsius (almost 2 degrees Fahrenheit) by 2019 has come to pass. His warning, and appeals for action from Hansen and others, went largely ignored by policymakers, despite an avalanche of confirmatory research from ensuing generations of climate scientists. We wanted to know: Who are the scientists who have dedicated their lives to studying the climate, knowing that their work may go unheeded and do little to avert a climate catastrophe? And how do they deal with it? As one of them said: "I have a mountain of data on my shoulders, but I feel so powerless."

Even the coronavirus pandemic has laid bare the enormous challenges the scientists confront. Echoing divisive skirmishes over climate change, politics and science have done battle, as some governments appeared to dismiss or minimize established research on the virus' spread. And despite a drop of 7% in emissions last year as the world ground almost to a halt, carbon dioxide levels continued to rise and are higher than at any point in human history. No year was hotter than 2020. It's a reminder that even as the tumultuous events of the past year grabbed headlines, climate change relentlessly thrummed in the background. The Siberian tundra is thawing as the Arctic sees record-breaking temperatures. Australia and California have burned and will burn again. Tropical storms are bigger and stronger than ever.

To structure this exploration of the world's top climate scientists, data journalist Maurice Tamman created a system of identifying and ranking climate academics according to how influential they are: how much they've published, how often those papers have been cited relative to others in the same field, and how often those papers have been referenced in the lay press, social media and other public policy papers. We call it the Hot List.

It's important to note that this isn't a ranking of the "best" climate scientists. It's a measure of influence, which naturally evolves over time, based on information available as of December 2020. The data was provided by the British-based company Digital Science, made available through its Dimensions portal. This effort examined at least 350,000 papers, 99% of which were published after Hansen's famous testimony. It has yielded a list of 1,000 top scientists – dominated by men working for Western institutions. From this list, we've selected six, four men and two women, whose stories capture the sweep of climate science today. These are not just stories about science, though, but about the people behind science.

You'll visit them at home, in places as far apart as Thuwal, Saudi Arabia, and Melbourne, Australia. You'll holiday with one on Block Island, off the Northeast U.S. coast. You'll see one in the water, at work in the Great Barrier Reef. One of them likes to play bass guitar in a band made up of other scientists, while another sings in one of the world's largest amateur orchestral choirs. One advises Saudi Crown Prince Mohammed bin Salman, while another played a hand in the environmental awakening of the late British Prime Minister Margaret Thatcher. One went into hiding after falling out of favor with the Iranian Revolutionary Guard. One used a 100,000-year-old chunk of Antarctic ice in a gin and tonic.

This year, there is renewed hope for action on stemming the causes of climate change. After a four-year American retreat, new U.S. President Joe Biden is promising to re-engage on this existential issue. Many of the world's largest fuel users and producers – including China, most European countries and even Saudi Arabia – have pledged significant reductions in carbon dioxide over the next 30 years. If the world's nearly 200 nations are going to act, it is these scientists' work that will gird the decisions and choices. These are their stories.

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)