Bad Estimates

May 3, 2021 at 10:55 am

People are bad at esti­mat­ing. We over­sim­pli­fy to get faster answers. We aver­age out com­plex­i­ties because they can’t fit neat­ly into our model. Unresolved prob­lems are uncom­fort­able. It’s incon­ve­nient to wait for data so we quick­ly move things along. We cre­ate starter solu­tions. We label things work in progress. We pro­pose tem­po­rary solu­tions and acknowl­edge that things will change over time as we col­lect more infor­ma­tion. We say we’ll get bet­ter as we go along.

Then, iner­tia takes over. The first takes become the stan­dard. The imper­fect model morphs into guide­lines and “the way it’s always been done.” Systems are built around the orig­i­nal find­ings. When the rest of the data comes in, when base assump­tions are proven as flaws, when extra exter­nal fac­tors are includ­ed — it’s no longer seen as a progress of knowl­edge, but as a chal­lenge to convention.

Here are two such chal­lenges I found this week­end. Carbon off­set cred­its for pre­serv­ing for­est land are com­ing up short on the amount of car­bon diox­ide they actu­al­ly sequester. The real estate mar­ket in the United States is not prop­er­ly account­ing for flood zones.

That’s because the state was using aver­ages to esti­mate how much CO2 each par­cel of for­est could hold. In real­i­ty, some pieces of for­est can store more than oth­ers based on what kinds of trees are there and how dense the for­est is. Forest man­agers also “gamed the sys­tem” by sell­ing cred­its from parcels that inflat­ed how much car­bon they stored, ProPublica and MIT Technology Review reported.

By Justine Calma at The Verge

Our find­ings indi­cate that hous­es in flood zones in the United States are cur­rent­ly over­val­ued by a total of $43.8 bil­lion (95% con­fi­dence inter­val: $32.6 to $55.6 bil­lion) based on the infor­ma­tion in pub­licly avail­able flood haz­ard maps alone, rais­ing con­cerns about the sta­bil­i­ty of real estate mar­kets as cli­mate risks become more salient and severe.

The effect of infor­ma­tion about cli­mate risk on prop­er­ty values

3.6 Million Years

April 12, 2021 at 3:00 pm

While falling down the Thwaites Glacier hole this morn­ing, there was more cli­mate change news released last week. The num­bers are star­tling, dead­en­ing, and make me stum­ble to find words. We made mil­lion year changes in just one hun­dred. We’ve reshaped the world and don’t even know — or can imag­ine — how yet.

The atmos­pher­ic bur­den of CO2 is now com­pa­ra­ble to where it was dur­ing the Mid-Pliocene Warm Period around 3.6 mil­lion years ago, when con­cen­tra­tions of car­bon diox­ide ranged from about 380 to 450 parts per mil­lion. During that time sea level was about 78 feet high­er than today, the aver­age tem­per­a­ture was 7 degrees Fahrenheit high­er than in pre-industrial times, and stud­ies indi­cate large forests occu­pied areas of the Arctic that are now tundra. 

National Oceanic and Atmospheric Administration Research
Global monthly mean carbon dioxide, December 2020 414.49ppm, two charts showing increases in CO2, chart one is from 2016-2020, chart two is from 1980-2020