Independent satellite records have confirmed ground data showing the past five years to be the hottest on record globally, scientists announced last week. It's another outcropping in the mountain of evidence that earth's climate is being fundamentally altered by human activity.
Yet in the United States, efforts to reduce the human contribution to climate change remain mired in ideological obstinance by leaders who dismiss it as a problem or think that other priorities should take precedence. The satellite evidence underscores the need to treat global warming as a top priority.
Scientists have long known that modern human industrial activity has produced higher concentrations of greenhouse gases in the atmosphere than at any time in at least the past 800,000 years, based on ice core samples. They've also established that, in the relatively tiny sliver of time coinciding with industrialization, average global temperatures have risen beyond anything humanity has seen before. The current century is the hottest yet.
Human-caused climate change today is only a controversy in the political sense. Scientifically, there is little disagreement about what's happening because the data is overwhelming. This is real.
Yet many conservatives, egged on by President Donald Trump, have relentlessly resisted accepting climate facts — not because they aren't factual, but because the solutions, including weaning ourselves from fossil fuels, are viewed as a threat to industrial and economic interests.
Their argument doesn't make significantly more sense than denying that a burning house is actually on fire because you don't want to expend the water necessary to put it out.
Measuring global temperature trends is a complicated business, requiring coordination of data from all over the world while accounting for variations in terrain, methodology and other issues. Climate-change skeptics have used that complexity to argue that scientific conclusions based on those coordinated ground readings shouldn't be believed because there's no independent way to verify them.
Except, now there is. The newly announced data from NASA's Aqua satellite, in orbit since 2002, has produced a 16-year, globe-spanning record of Earth's temperature trends, using infrared technology that is more accurate than many ground-level methods.
NASA announced that the data tracks almost exactly with the earlier information scientists used in proclaiming the past five years as the hottest on record. As one researcher explained to The Washington Post: "These findings should help put to rest any lingering concerns that modern warming is somehow due to ... measurement errors at the surface."
That probably won't sway the ideologues, who shun real scientific data the same way anti-vaccination fanatics ignore warnings of a growing measles epidemic. But for those who understand this isn't an ideological issue but a scientific one, the latest data should drive home the need to address this as the existential threat to humanity that it is.
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