world's largest climate change experiment

[mellowtigger]

It's been 3.5 years since my chapter last met at an all-staff retreat. This time, we met at Sugar Lake Lodge in northern Minnesota. Once again, my full-time counterpart rented the car to drive us there and back.  It is a nice location. The morning scenery included fog blowing through the small hills and across the lake. The food was good. I slept quite soundly in the quiet environment, much better than the loud area where I live. Cell phone reception, however, was so bad that I had to put my phone in airplane mode to prevent it from draining the battery in a matter of hours.

The highlight for me was the field trip. We had 3 to choose from, and I selected the Marcell Experimental Forest. The particular experiment that we visited was the Spruce and Peatland Responses Under Changing Environments (SPRUCE) facility that they describe as the largest climate change experiment in the world. Curiously, SPRUCE is funded through the Department Of Energy, as part of their effort to trace carbon in the ecosystem and it's effect on climate.

As part of the Trump and Republican war on knowledge, our field guides said that their funding was eliminated as Trump entered office, because it contained the word "climate" in it. They changed their name, reapplied, and got their funding restored. I've been trying to track down which program/site/fund had to change names, and I'm not having any luck identifying it yet. So I'll just use the current names, since I can't find the original nomenclature (which was probably more accurate instead of being now literally "politically correct").

The SPRUCE site is set on a bog in Minnesota. Peatlands account for only 3% of land surface, but they account for 30% of soil (not above-surface) carbon. If bogs change from carbon-sinks to carbon-sources, it would have a huge effect on global warming. So the SPRUCE facility selected 16 locations for monitoring. At each site, they have a series of instruments at different heights for ground temperature, air temperature, CO2 concentration, tree metabolism, and tree circumference. They watch native plants already growing at each site to monitor how they react to different temperatures and CO2.

Here's the kicker. Around many of the sites, they built octagonal "containment units" with translucent 8-meter (26-feet) walls and an open ceiling. Within the units, they alter the ground temperature, air temperature, and CO2 concentration (up to 900ppm). Measurements are taken at some of the control units, and once each minute they make adjustments to the controlled units. The unit that we walked into was the highest relative temperature, +9C (16.2F) above the ambient temperature.

It takes a whole lot of propane to keep the many vents blowing to maintain the relative temperature difference 24 / 7 / 365. They had 4 big propane tanks on site. They told us they burned 1 tank each week in summer and 2 tanks in winter. That's a huge carbon footprint for a facility meant to explore the impact of atmospheric carbon dioxide on the biome. Our guides called attention to the irony.

It seemed a well designed site.  They even have visual/auditory CO2 alarms in case concentrations within an enclosure reach deadly levels for humans, so anyone inside would immediately know to exit.  I envy the infrastructure they were able to provide. At first, I was surprised to find such a facility located within Minnesota. But Minnesota's temperature has already risen 2.5-3 degrees since 1970, with most of that change affecting our winter season. We have lots of bog, fen, marsh, and swamp, so I guess it really does make a lot of sense to locate this facility here.

They continuously collect data. There's a set of panels outside where networking is provided, so they get a flow of information from each of the units. They also monitor some units that are the experimental controls. Those control units have the same monitors but no environmental changes and maybe even no walls.



It was fascinating.  It's good to know that another dataset of solid evidence will be added to future climate estimations.  They still need to do similar research for permafrost, but science seems to be doing a good job narrowing our uncertainty.  It may still be too little, too late, but for now I'm feeling a bit more optimistic.  It seems like every time they refine their models with new data, the results are even more dire.  My current optimism assumes, of course, that we can continue collecting data under the management of a political party that's determined to remain ignorant of these and other observations.  It's unfortunate that we have to organize protest marches for that kind of thing these days.  But my mood today, nevertheless, is slightly optimistic.