Jason Hamilton Thomas J. Pfaff. Glacier Pair Images ier_then_now.pdf

Inflection Points and Polar Bears

Jason HamiltonThomas J. Pfaff

0 10 20 30 40 50 60 7013.20

13.40

13.60

13.80

14.00

14.20

14.40

14.60

14.80

15.00f(x) = 0.000278381926013931 x² − 0.00290301903785536 x + 13.9651003056405R² = 0.803909460802452

Average Global Temp in C by Years after 1950

Glacier Pair Imageshttp://www.windows.ucar.edu/

teacher_resources/glacier_then_now.pdf

A Look at Global Temperature

T(x)=0.0005x2 -0.00527x+57.137 FT’(x)=0.001x-0.00527 F/year

x years after 1950

T(58)= 58.51 F and T’(58)=0.0528 F/yearIn 2008 the average global temperature was

58.51 deg F and increasing at a rate of 0.0528 deg F per year.

- Now Ask a Question About This-

National Academies Report: Climate Change

The rising temperature observed since 1978 are particularly noteworthy because the rate of increase is so high and because, during the same period, the energy reaching the Earth from the Sun had been measured precisely enough to conclude that Earth’s warming was not due to changes in the Sun.

-March 2006

Temperature PredictionsT(100)=61.60 F and T(150)=67.61 FThe model predicts that in 2050 the average

temperature will be 61.6 deg F, and in 2100 it will be 67.61 deg F, an increase of 3.49 and 9.48 deg F, respectively, since 2000.

–Now Ask a Question About This-

More Temperature PredictionsUsing T’(58)=.0528 F/yearIf global temperatures continue to increase

at current rates, then by 2050 there will be an increase of 2.61 deg F and by 2100 there will be an increase of 5.24 deg F since 2000. The average global temperature in those years will be 60.73 and 63.37, respectively.

0 10 20 30 40 50 60 7053

54

55

56

57

58

59

Average Global Temp in F by Years after 1950

-National Academies Report on Climate Change (March 2006)

0 2 4 6 8 10 12 140

2

4

6

8

10

12

14

16

18

f(x) = − 0.000654276 x⁶ + 0.02264835 x⁵ − 0.29305592 x⁴ + 1.81852903 x³ − 6.00367805 x² + 10.081854 x + 8.39787879R² = 0.983310019501055

f(x) = − 0.00029262 x⁶ + 0.0097127 x⁵ − 0.11862834 x⁴ + 0.70835403 x³ − 2.55757499 x² + 5.25739536 x + 11.6584848R² = 0.996794192382088

Arctic Sea Ice Extent by Month in Million Square Kilometers

1980 extent in million square kmPolynomial (1980 extent in million square km)2008 extent in million square kmPolynomial (2008 extent in million square km)

Summary of Sea Ice1980

Max: 16.13 msk, x=2.59

Min: 7.86 msk, x=8.79

Inf: -2.20 msk/month, x=6.44

Melt Period: 6.20 months

2008Max: 15.11 msk,

x=2.26Min: 5.40 msk,

x=8.80Inf: -2.84

msk/month, x=6.77Melt Period: 6.54

months

Who Cares? D Heat content of atmosphere & hydrosphere

D Air Temperature & D Water Temperature

D Ice

D Ice•Spatial Extent?•Thickness?•Timing of thaw?•Timing of re-freeze?•Ice characteristics?

January

Sept March

June

Thaw

Freeze

Shrink

Grow

Males

January

Sept March

June

Thaw

Freeze

Den

Females

Leave den

Cubs

Mate

So Who Cares? We Do.

?

Questions?Jason: jhamilton@ithaca.eduTom: tpfaff@ithaca.edu

Partly supported by NSF DUE-0837721