I’m auditing the EdEx course “Denial101x: Making Sense of Climate Science Denial.” This is Week 2: Global Warming ins Happening. The course is covering indicators of warming, what is happening in the Cryosphere, and related matters.
Here is an example lecture segment:
A central theme of this week is the relationship between climate and weather, and how this relationship becomes fodder for the development of myths in service of denial about climate change. The climate is a cherry orchard. Weather is the cherries. Don’t pick the cherries!
There are many dimensions the climate system that allow cherry picking. You can look at local temperature records and see very little warming in some placs. You can look at different levels of the atmosphere, and you can ignore the oceans. Don’t ignore the oceans, that is where most of the heat imbalance caused by anthropogenic greenhouse gas pollution plays out.
At one point in this week’s course, you get to play with a really cool data tool. Like this:
Playing around with that tool is very fun and informative, and the process is backed up with some excellent information about how the data set(s) work(s).
Cherry Picking, Setting False Expectations, How records are made and tracked (we are setting hot records more often than cold records over recent decades, in the US and elsewhere). Global warming is analogous to rigging the climate dice.
Sea level rise, thermal expansion of the global ocean, melting glacial ice. Glaciers are losing about 150 billion tonnes of ice a year, accelerating. Many mountain glaciers have disappeared or shrunk a great deal. Annual mass balance. Tracking glacier history. Myth: Some glaciers are growing therefore there is no global warming (cherry picking, there are a few growing glaciers due to warming causing more snow locally).
Greenland ice loss: Over 300 billion tonnes per year, or 6 meters of ocean if all melted. Moulins. Ice shelves as corks. Gaining ice in interior. Greenland is already at 2 degrees C surface air increase. Largest individual contributor to sea level rise. Myth: Since ice is building up in the interior (ignoring the rest of the region) global warming is not real. Note: Most of the accelerated melt is very recent, mass balance has been negative for about 15 years, and this is increasing. Get waders.
Antarctica, west and east (largest, oldest). Total contribution to global sea level if all melted = 72 meters. Recently discovered that WAIS is more sensitive to climate change than previously thought. Melt started in recent decades and is accelerating, in WAIS. EAIS relatively stable. (But this is questionable, may be changing.)
Antarctic sea ice: Seasonal, does not influence climate much. Myth: sea ice increase means global warming not real. Winds may blow sea ice outwards, so open water freezes, and the winds blow colder water. Fresh meltwaters easier to freeze. Snow fall increased.
Land and sea ice are totally different things. Myth of sea ice discounting global warming is cherry picking and error of omission.
Excellent in depth interview with several ice experts. It is worth looking at these longer interviews even if they are not on the quiz!
Building the temperature record (How do we measure global warming). Myths: Thermometers not reliable, insufficient in number. Jumping to conclusions … scientists estimate error, the error is way smaller in magnitude than the temperature increase signal. Multiple methods of measurement agree with each other.
Urban heat island effect. Neat: Compare light pollution with heat island effect. They don’t match up, suggesting HIE is very local and not strong. NASA matching of paired rural/urban stations: effect is small. Other studies support this. Fallacy: Jumping to conclusions. Going from a reasonable hypothesis to the conclusion, meanwhile actual scientists examined the hypothesis and found it wanting. Myth: “Corrections” are bogus (jumping to conclusions). Truth: Corrections are proper adjustments to data. Ie when you change instruments or move instruments an adjustment or calibration may be necessary. Comparing adjusted vs. non adjusted data shows that the adjustments, while justified, don’t change the numbers much.
Wavy Jet Streams. How hey work. Myth: “It’s cold out, so much for global warming!” Cherry Picking, that. GLOBAL warming.
How jet streams form and why they get wavy. Arctic amplification (positive feedback from ice/snow cover changes, etc.). So tropical/polar temp gradient (and thus pressure gradient) reduces, waves and slower jet streams result.
“Climate Change” vs. “Global Warming.” Myth: Some bogus story about how scientists are playing a fast one. Personally, I prefer Obamacare over the Affordable Care Act. (FLICC type: Conspiracy Theory. Over Simplification.)