Scientists are trained to be professional skeptics: to always judge the validity of a claim or finding on the basis of objective, empirical evidence. They are not cynics; they just ask themselves and each other a lot of questions.

If they see a claim that a finding is true, they will ask: “Why?” They may hypothesize that if that finding is true, then some related findings must also be true. If it’s unclear whether one or more of those other findings is true, they will do more work to find out.

It is no wonder that science moves so slowly, especially on really important topics such as climate change.

Dogmatism is the opposite of skepticism. It is the proclivity to assert opinions as unequivocally true without taking account of contrary evidence or the contradictory findings. It is why public debate over scientific findings never seems to go away.

An example of the difference is the reaction to the Intergovernmental Panel on Climate Change’s finding in 1995 that “evidence suggests a discernible human influence on global climate.” The IPCC’s assessment reports involve hundreds of researchers from around the world who reviewed the global scientific understanding of the planet’s changing climate.

It’s an instructive case in the differences between skepticism and dogmatism, and it’s something to think about as you hear people talk about climate change.

Origins of a dogmatic response

Shortly after the IPCC released that finding in 1995, persistent and well-organized attacks on the science began. Many came from groups supported by the owners of Koch Industries, a conglomerate involved in oil refining and chemicals.

Their strategies mimicked earlier assaults on science and scientists who had warned the public that smoking posed a serious threat to their health. This time it was a warning about fossil fuels’ impact on the climate.

The similarity should not be a surprise. Science historians Naomi Oreskes and Erik Conway, in their 2011 book “Merchants of Doubt,” and American historian Nancy MacLean, in her 2010 book “Democracy in Chains,” have explained how the strategy was written by some of the same people who had tried to stop efforts to tighten tobacco regulations a decade or so earlier.

The dogma presented to the public for fighting regulation held that personal freedoms are paramount and that they are not to be diminished by any efforts designed explicitly to improve the general welfare.

What a skeptical response looks like

Climate scientists understood in 1995 that they must provide more than laboratory results, which go back to Svante Arrhenius’ work in 1895 demonstrating a causal correlation between increasing carbon dioxide concentrations and rising temperatures.

They also accepted the challenge of exploring collections of associated effects that should also be true if human activity was changing the climate.

Scientists have since examined dozens of different independently monitored aspects of climate change and confirmed the expected fingerprints of climate change all around the world.

Since the upper layers of the oceans absorb 90% of the atmosphere’s excess heat, they should be persistently warming as global temperatures rise. Has that happened? Yes, it has.

Since land-based ice melts when temperatures get too warm, global sea level should rise. And it should rise by more than would happen with thermal expansion of warming ocean water alone. Is it? Data shows that it is.

Syukuro Manabe and Richard Wetherald argued in 1967 that the upper atmosphere should cool while surface temperatures rise in response to higher carbon dioxide concentrations. Has it cooled over the past 50 years? Yes, it has, just as Manabe predicted.

By 2021, as the evidence piled up, the IPCC’s Sixth Assessment stated: “It is unequivocal that human influence has warmed the global climate system since pre-industrial times. Combining the evidence from across the climate system increases the level of confidence in the attribution of observed climate change to human influence and reduces the uncertainties associated with assessments based on single variables. Large-scale indicators of climate change in the atmosphere, ocean, cryosphere and at the land surface show clear responses to human influence consistent with those expected based on model simulations and physical understanding.”

Convincing the public

But has the public been convinced? The data on this is mixed.

Annual surveys conducted by the Yale Program on Climate Change Communication have found that the percentage of Americans “alarmed” about climate change rose over the past 11 years – from 15% in 2014 to 26% in 2024. And they show that much of that increase came from an increase in concern among Americans who earlier considered themselves “concerned” or “cautious.”

Over the same time period, though, the proportion of citizens in the survey who considered themselves “disengaged,” “doubtful” or “dismissive” shrank only modestly, from 29% to 27%.

Other surveys suggest that personal experience likely plays a significant role in how people understand climate change.

Many local and national news stations have mentioned climate change as a contributing factor in their extensive coverage of destructive wildfires in Los Angeles and Hawaii, flash floods in North Carolina and Texas, persistent drought across the Southwest, extreme heat waves and destructive hurricanes.

Some of their viewers could certainly be coming around to believing what evidence shows: that climate-related disasters have become more frequent and more intense.

Americans are also directly experiencing other effects of climate change on their homes, health and wallets. For example:

• Doctors in the North are seeing increasing cases of Lyme disease. Those in the South have been witnessing a rising number of cases of dengue fever. Both are spread by insects whose ranges are expanding as temperatures rise.

• Lobster populations have collapsed in Long Island Sound and flourished farther north in Canada’s Bay of Fundy.

• Residents in southern New England now enjoy feeding bluebirds in winter.

• Homeowners across the U.S. are seeing their property insurance premiums quickly rise as disaster risks increase. Many others can’t get coverage from insurance companies at all because of their area’s disaster risks.

Stories like these do not make the national news very often, but they do show up in conversations around the kitchen table.

Reaching those with dismissive views

So, how can those Americans who are dismissive of climate change be reached? Some dogmatically believe claims that “climate change is a hoax” despite ever-growing evidence to the contrary.

Talking about personal experiences with extreme weather events, wildfires or droughts and their connections to rising global temperatures can help.

It might also help to remind them of failed dogma from the past that was disproved by science, yet people continued for years to believe them. For example, we know today that the Earth is not flat, the Sun does not circle the Earth, and living organisms cannot materialize spontaneously from nonliving matter.

The shift in public perceptions of climate risks leaves me hopeful that more people are acknowledging the scientific understanding of climate change and catching up with the climate scientists who have produced, questioned, reexamined and reaffirmed their findings through rigorous application of the scientific method.

Gary W. Yohe, Professor of Economics and Environmental Studies, Wesleyan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Arctic is transforming faster and with more far-reaching consequences than scientists expected just 20 years ago, when the first Arctic Report Card assessed the state of Earth’s far northern environment.

The snow season is dramatically shorter today, sea ice is thinning and melting earlier, and wildfire seasons are getting worse. Increasing ocean heat is reshaping ecosystems as non-Arctic marine species move northward. Thawing permafrost is releasing iron and other minerals into rivers, which degrades drinking water. And extreme storms fueled by warming seas are putting communities at risk.

The past water year, October 2024 through September 2025, brought the highest Arctic air temperatures since records began 125 years ago, including the warmest autumn ever measured and a winter and a summer that were among the warmest on record. Overall, the Arctic is warming more than twice as fast as the Earth as a whole.

For the 20th Arctic Report Card, we worked with the National Oceanic and Atmospheric Administration, an international team of scientists and Indigenous partners from across the Arctic to track environmental changes in the North – from air and ocean temperatures to sea ice, snow, glaciers and ecosystems – and the impacts on communities.

Together, these vital signs reveal a striking and interconnected transformation underway that’s amplifying risks for people who live there.

A wetter Arctic with more extreme precipitation

Arctic warming is intensifying the region’s water cycle.

A warmer atmosphere increases evaporation, precipitation and meltwater from snow and ice, adding and moving more water through the climate system. That leads to more extreme rainstorms and snowstorms, changing river flows and altering ecosystems.

The Arctic region saw record-high precipitation for the entire 2025 water year and for spring, with the other seasons each among the top-five wettest since at least 1950. Extreme weather – particularly atmospheric rivers, which are long narrow “rivers in the sky” that transport large amounts of water vapor – played an outsized role.

These wetter conditions are reshaping snow cover across the region.

Snow and ice losses accelerate warming, hazards

Snow blankets the Arctic throughout much of the year, but that snow cover isn’t lasting as long. In 2025, snowpack was above average in the cold winter months, yet rapid spring melting left the area covered by snow far smaller than normal by June, continuing a six-decade decline. June snow cover in recent years has been half of what it was in the 1960s.

Losing late spring snow cover means losing a bright, reflective surface that helps keep the Arctic cool, allowing the land instead to be directly warmed by the sun, which raises the temperature.

Sea ice tells a similar story. The year’s maximum sea ice coverage, reached in March, was the lowest in the 47-year satellite record. The minimum sea ice coverage, in September, was the 10th lowest.

Since the 1980s, the summer sea ice extent has shrunk by about 50%, while the area covered by the oldest, thickest sea ice – ice that has existed for longer than four years – has declined by more than 95%.

The thinner sea ice cover is more influenced by winds and currents, and less resilient against warming waters. This means greater variability in sea ice conditions, causing new risks for people living and working in the Arctic.

The Greenland Ice Sheet continued to lose mass in 2025, as it has every year since the late 1990s. As the ice sheet melts and calves more icebergs into the surrounding seas, it adds to global sea-level rise.

Mountain glaciers are also losing ice at an extraordinary rate – the annual rate of glacier ice loss across the Arctic has tripled since the 1990s.

This poses immediate local hazards. Glacial lake outburst floods – when water that is dammed up by a glacier is suddenly released – are becoming more frequent. In Juneau, Alaska, recent outburst floods from Mendenhall Glacier have inundated homes and displaced residents with record-setting levels of floodwater.

Glacier retreat can also contribute to catastrophic landslide impacts. Following the retreat of South Sawyer Glacier, a landslide in southeast Alaska’s Tracy Arm in August 2025 generated a tsunami that swept across the narrow fjord and ran nearly 1,600 feet (nearly 490 meters) up the other side. Fortunately, the fjord was empty of the cruise ships that regularly visit.

Record-warm oceans drive storms, ecosystem shifts

Arctic Ocean surface waters are steadily warming, with August 2025 temperatures among the highest ever measured. In some Atlantic-sector regions, sea surface temperatures were as much as 13 degrees Fahrenheit (7.2 Celsius) above the 1991-2020 average. Some parts of the Chukchi and Beaufort seas were cooler than normal.

Warm water in the Bering Sea set the stage for one of the year’s most devastating events: Ex-Typhoon Halong, which fed on unusually warm ocean temperatures before slamming into western Alaska with hurricane-force winds and catastrophic flooding. Some villages, including Kipnuk and Kwigillingok, were heavily damaged.

As seas warm, powerful Pacific cyclones, which draw energy from warm water, are reaching higher latitudes and maintaining strength longer. Alaska’s Arctic has seen four ex-typhoons since 1970, and three of them arrived in the past four years.

The Arctic is also seeing warmer, saltier Atlantic Ocean water intrude northward into the Arctic Ocean. This process, known as Atlantification, weakens the natural layering of water that once shielded sea ice from deeper ocean heat. It is already increasing sea ice loss and reshaping habitat for marine life, such as by changing the timing of phytoplankton production, which provides the base of the ocean food web, and increasing the likelihood of harmful algal blooms.

From ocean ‘borealization’ to tundra greening

Warming seas and declining sea ice are enabling southern, or boreal, marine species to move northward. In the northern Bering and Chukchi seas, Arctic species have declined sharply – by two-thirds and one-half, respectively – while the populations of boreal species expand.

On land, a similar “borealization” is underway. Satellite data shows that tundra vegetation productivity – known as tundra greenness – hit its third-highest level in the 26-year record in 2025, part of a trend driven by longer growing seasons and warmer temperatures. Yet greening is not universal – browning events caused by wildfires and extreme weather are also increasing.

Summer 2025 marked the fourth consecutive year with above-median wildfire area across northern North America. Nearly 1,600 square miles (over 4,000 square kilometers) burned in Alaska and over 5,000 square miles (over 13,600 square kilometers) burned in Canada’s Northwest Territories.

Permafrost thaw is turning rivers orange

As permafrost – the frozen ground that underlies much of the Arctic – continues its long-term warming and thaw, one emerging consequence is the spread of rusting rivers.

As thawing soils release iron and other minerals, more than 200 watersheds across Arctic Alaska now show orange discoloration. These waters exhibit higher acidity and elevated levels of toxic metals, which can contaminate fish habitat and drinking water and impact subsistence livelihoods.

In Kobuk Valley National Park in Alaska, a tributary to the Akillik River lost all its juvenile Dolly Varden and slimy sculpin fish after an abrupt increase in stream acidity when the stream turned orange.

Arctic communities lead new monitoring efforts

The rapid pace of change underscores the need for strong Arctic monitoring systems. Yet many government-funded observing networks face funding shortfalls and other vulnerabilities.

At the same time, Indigenous communities are leading new efforts.

The Arctic Report Card details how the people of St. Paul Island, in the Bering Sea, have spent over 20 years building and operating their own observation system, drawing on research partnerships with outside scientists while retaining control over monitoring, data and sharing of results. The Indigenous Sentinels Network tracks environmental conditions ranging from mercury in traditional foods to coastal erosion and fish habitat and is building local climate resilience in one of the most rapidly changing environments on the planet.

The Arctic is facing threats from more than the changing climate; it’s also a region where concerns of ecosystem health and pollutants come sharply into view. In this sense, the Arctic provides a vantage point for addressing the triple planetary crisis of climate change, biodiversity loss and pollution.

The next 20 years will continue to reshape the Arctic, with changes felt by communities and economies across the planet.

Matthew L. Druckenmiller, Senior Scientist, National Snow and Ice Data Center (NSIDC), Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder; Rick Thoman, Alaska Climate Specialist, University of Alaska Fairbanks, and Twila A. Moon, Deputy Lead Scientist, National Snow and Ice Data Center (NSIDC), Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder

This article is republished from The Conversation under a Creative Commons license. Read the original article.