Climate scientists–and other scientists–are always improving and updating their methods. That’s how science works. And it’s a very good and honorable thing–or at least, it is until conservatives catch on to some particular methodological change and argue that it’s political, rather than part of the normal course of scientific events.
And until Fox News–whose viewers are far less likely to accept climate science, as well as various other well known facts–joins in.
In the latest case, a group at the University of Colorado at Boulder added a new correction to their estimates of global sea level rise. What they did is pretty technical, but before going further I’ll have to briefly explain it—more details can be found here.
A correction for glacial isostatic adjustment—or GIA—was recently added to the Colorado group’s estimates of the rate of sea level rise. This was done because even as sea level is rising (due to the thermal expansion of the oceans and the melting of land-based ice), the land in some areas is also rising a bit, increasing the size of the ocean basins. Why is the land rising? It’s a “rebound” from the disappearance of massive land based glaciers since the last ice age.
Any questions so far?
So the Colorado scientists added a correction to take into account GIA, so that they could measure–in isolation–how much total water volume is being added to the ocean. Due to the rising of land, this cannot be simply inferred from measuring the sea level along the coastline.
Here’s a somewhat comprehensible explanation from the University of Colorado website:
…we have to account for the fact that the ocean is actually getting bigger due to GIA at the same time as the water volume is expanding. This means that if we measure a change in [global mean sea level] of 3 mm/yr, the volume change is actually closer to 3.3 mm/yr because of GIA….We apply a correction for GIA because we want our sea level time series to reflect purely oceanographic phenomena. In essence, we would like our [global mean sea level] time series to be a proxy for ocean water volume changes. This is what is needed for comparisons to global climate models, for example, and other oceanographic datasets.
Okay. Perfectly normal, perfectly justifiable.
However, as we know, climate science is watched closely by conservatives, who are looking for places where they can cry foul and object. And in this case, along comes the Heartland Institute’s James M. Taylor, who says the scientists have “doctor[ed]” their data:
Note: Taylor himself admits that the consequences of this correction will only be “1.2 inches over the course of the 21st century.” In other words, if sea level rise is a big deal, then the correction in question certainly isn’t.
But we’re not done yet. Now comes Fox News and its reporter Maxim Lott, who does an “on the one hand, on the other hand” piece about whether the GIA correction is kosher. Suddenly it’s the scientists at Colorado vs. Taylor:
Taylor calls it tomfoolery.
“There really is no reason to do this other than to advance a political agenda,” he said.
Actually, we’ve already seen the entirely non-political reason to do this.
But we’re still not done. Then Matt Drudge takes up the story, adds some more bias and some embellishment—“Climate change ‘researchers’ caught padding sea level data”—and off it goes. Another byte of misinformation about climate change is now in circulation.
What’s tragic about all of this? Sea level is really rising, and the rate is expected to increase—and adjusted or unadjusted, corrected or uncorrected, this is one of the most transformative aspects of climate change.
