People who reject the scientific consensus on human-caused climate change often argue that “the climate has always changed.” This is said as though it is proof that we have no reason to be concerned about the increasing weather extremes we are observing today.

Deniers of climate change are right that the climate has always changed. But they are wrong—dangerously so—to conclude that we have little reason to be concerned. Every week or so a new study is released giving us new reason for concern. If we are not convinced by those studies—or if we are not aware of them, surely the heat wave in the Pacific Northwest, the worsening wildfires throughout much of the West, and the unprecedented early storms coming into the Gulf should give us good reason to pay attention.

As a result of climate change, some regions of our Earth are becoming scorched to the point of becoming uninhabitable. As long-time student of climate science Peter Brannen wrote in the March issue of the Atlantic magazine, “Humanity’s ongoing chemistry experiment on our planet could push the climate…into a new state it hasn’t seen in tens of millions of years, a world for which Homo sapiens did not evolve.”

We humans have no collective memory of a time when the atmosphere held 410 parts per million of carbon dioxide—today’s level, and rising. But the science of paleoclimatology tells us that when the atmosphere had 400 ppm of CO2—more than 3 million years ago—the world was 5 to 9 degrees F. warmer than today and sea level was 80 feet higher. The U.N. World Meteorological Organization estimates that, at the current rate of temperature increases caused primarily by burning fossil fuels, global temperatures are on track to increase by this much during this century. In other words, if we do not reduce our burning of fossil fuels soon, we could see temperatures rise to levels not seen for more than 3 million years. Yes, the climate is always changing.

One of the main lessons of recent climate science is that small changes in warming can cause “nonlinear” climate responses well beyond climate model projections. The exceedingly high temperatures in the Pacific Northwest and British Columbia in late June and early July present new evidence of a more aggressive climate response. Several hundred deaths are attributed to the heat wave, which also caused deadly wildfires.

A World Weather Attribution study of this heat wave concluded that it was “virtually impossible without human-caused climate change.” The study is based on newer methodologies that enable scientists to more accurately link extreme weather events to global warming.

The study concludes with this warning: “The future will be characterized by more frequent, more severe, and longer heatwaves, highlighting the importance of significantly reducing our greenhouse gas emissions to reduce the amount of additional warming.”

Warnings like this can be heeded or ignored. In the case of the collapsed condo tower in Surfside, FL, there were warnings years ago of “major structural damage” to the building’s foundation, damage in which sea-level rise and seeping water caused by climate change may have been a factor. Tragically, the warnings by engineers were ignored.