We know it’s getting warmer. Earth’s climate has changed naturally over thousands of years—through cycles of ice ages and warmer periods driven by subtle shifts in the planet’s orbit. But what we’re experiencing today is different. The current warming trend is faster, more intense, and clearly linked to human activity. Since the mid-1800s, the burning of fossil fuels like coal, oil, and gas—along with large-scale deforestation—has caused heat-trapping gases such as carbon dioxide and methane to accumulate rapidly in the atmosphere. These greenhouse gases are blanketing the Earth and intensifying the natural greenhouse effect, locking in more of the Sun’s energy.
As a result, every decade since the 1960s has been hotter than the one before, and the impacts are visible not just in rising temperatures, but across our oceans, ice sheets, and ecosystems. The Intergovernmental Panel on Climate Change (IPCC) confirms that human influence on the climate system has evolved from theory to established fact.
From shrinking glaciers to extreme weather patterns, here are 9 unmistakable signs that prove climate change is real and happening now.
It’s no secret—our planet is getting warmer. Since the late 1800s, Earth’s average surface temperature has gone up by about 2°F (1°C). Most of that warming has happened in just the past 40 years. In fact, the seven hottest years ever recorded have all occurred since 2016, with 2016 and 2020 tied for the hottest year on record. The biggest driver? Carbon dioxide and other greenhouse gases released from burning fossil fuels, deforestation, and industrial activities.
The oceans are doing most of the heavy lifting when it comes to absorbing excess heat—about 90% of it, in fact. Since 1969, the upper 100 meters (about 328 feet) of ocean water has warmed by approximately 0.67°F (0.33°C). This steady increase might seem small, but when you're talking about that much water, the effects are massive—impacting marine life, weather systems, and global climate patterns.
Both Greenland and Antarctica are losing ice at an alarming rate. According to NASA data, Greenland is shedding around 279 billion tons of ice per year, while Antarctica is losing about 148 billion tons annually. These aren’t just numbers—they translate to rising sea levels, disrupted ocean currents, and less reflection of sunlight back into space (which normally helps keep the planet cool).
From the Alps to the Andes, the Himalayas to the Rockies, glaciers are retreating. These once-stable ice giants are now shrinking year after year due to warmer temperatures. For many communities that rely on glacial meltwater, this also means shrinking freshwater supplies.
Satellite data shows that spring snow cover in the Northern Hemisphere has steadily declined over the last 50 years. Not only is there less snow, but it’s also melting earlier in the year. This has huge effects on water availability, especially in areas that rely on snowmelt to feed rivers and reservoirs.
In the last 100 years, global sea levels have risen about 8 inches (20 centimeters). And here’s the worrying part: in just the past two decades, that rate has nearly doubled—and it continues to accelerate. Rising seas threaten coastal communities, ecosystems, and infrastructure all over the world.
Both the extent and thickness of Arctic sea ice have been declining rapidly over the past few decades. Less ice means more open water, which absorbs more sunlight and speeds up the warming even further—a dangerous feedback loop.
Across the globe—and especially in the United States—we’re seeing more record high temperatures and fewer record lows. On top of that, extreme rainfall events have become more frequent, often leading to flash floods, property damage, and crop loss. Climate change is making weather not just warmer, but also more unpredictable and more dangerous.
As we pump more carbon dioxide into the atmosphere, the ocean ends up absorbing a big chunk of it—about 20–30% of human-made emissions. This has caused a 30% increase in the acidity of surface ocean waters since the Industrial Revolution. That shift in pH harms coral reefs, shellfish, and countless other forms of marine life that depend on stable ocean chemistry.