von_Haden_Presentation

ENV S&P 701Adam von Haden10/20/09 : 

ENV S&P 701Adam von Haden10/20/09 “Maximizing Ecological Services and Economic Returns from Targeted Establishment of Biomass Grasslands for Electricity and Heat Generation in Wisconsin” Other science-related interests: Sustainable agriculture; reduction/elimination of pesticides Tropical forest restoration and conservation initiatives Other interests: Music “Metal” - Pantera, Tool, Megadeth, BLS, Clutch, Corrosion of Conformity, Down “Classic Rock” – Black Sabbath, Led Zeppelin, Beatles, Ozzy, Deep Purple, Rush “Jazz” - Herbie Hancock, Miles Davis, Pat Metheny, Frank Zappa, John Coltrane “Country” – Hank Williams III, Flying Burrito Brothers, the Byrds, Pure Prairie League

Chapter 12: Moore’s Law : 

Chapter 12: Moore’s Law Unquenchable – Robert Glennon

Semiconductor Transistors : 

Semiconductor Transistors Gordon Moore – cofounder of Intel Corp. "The number of transistors and resistors on a chip doubles every 18 months.” (1965)

Transistor Evolution : 

Transistor Evolution 1947 – 1 Transistor 2009 – ~2E9 Transistors (45 nm)

Water Usage : 

Water Usage Water use increased dramatically with increase in transistor capacity Original plan was to decrease water usage by using dry methods Many production plants in SW U.S. Would also reduce problems from groundwater contamination – arsenic, etc Easier to remove toxins and reuse the water

Water Recycling : 

Water Recycling Since 1998 has saved 20 billion gallons E.g. Intel plant decreases water production 75% 1 million gal day-1 vs. 5 million gal day-1 Several components to recycling: RO clean up → Return to aquifer Buy reclaimed water → Landscape, cooling, etc. Internal recycling plant → ultra-pure water Used to rinse and clean semiconductor wafers Increased grade of water = higher efficiency

Implications : 

Implications Companies like Intel depend on reliable water sources Available water will play a large role in industry Cost/benefit analysis: 135,000 gallons H2O per ton of alfalfa ($110) $0.0008 return per gallon of water < 10 gallons H2O per processor ($264) $26.40 return per gallon of water 50,000 X better return per unit water

Questions : 

Questions Is using the profit generated per unit of water a good way to determine the validity of the practice? What other factors need to be taken into consideration? Will Moore’s “Law” hold up forever?

Slide 9: 

Andrew Shepherd and Duncan Wingham Recent Sea Level Contributions of the Antarctic and Greenland Ice Sheets

Reasons for Concern : 

Reasons for Concern Water holding capacity Greenland and Antarctic ice sheets hold enough water to raise sea levels ≈ 70 m 1000X amount in the Great Lakes Dramatic changes have occurred in past 20 m change in < 500 years = 40 mm yr-1 Sea level is rising at ≈ 3.0 mm yr-1 Currently issues with the 20th century sea level budget I.e. some of the sea level rise is unaccounted for

Estimating Ice Budgets : 

Estimating Ice Budgets Use of a mass-budget method (mass balance) The earth can be considered a closed system Inputs vs. outputs = change Input: Snowfall Outputs: Sublimation, meltwater, ice flows Sounds pretty simple Difficult to measure most aspects Current estimates vary significantly -366 to +53 Gt/year

Mass Balance Results : 

Mass Balance Results Why is there so much variability? …

Methodologies : 

Methodologies InSAR – interferometric synthetic aperture radar To measure ice surface velocity (flow) Remote sensing using radar satellites Temporal changes in the phase of the wave at a given area indicates movement Problems: Lack of good precipitation and ice thickness data

Methodologies … : 

Methodologies … Precipitation (accumulation) estimation Ice core records or meteorological forecast models Only valid if surface melting is negligible (Antarctica) Problems: Large range of estimates (1475 – 2331 Gt yr-1) Differences in spatial interpolation Satellite-observed microwave temperature Correlates temperature with accumulation A ground truthing study placed the estimates within 5% Problems: Records only exist from 1995 Only 58% of Antarctica and 70% of Greenland have been surveyed

Methodologies … : 

Methodologies … Satellite/aircraft-based radar and laser altimetry Measure the wave travel time to determine distance Problems: Density of snow and ice differ by 3X Most data is from interior areas with high growth High variation in accumulation makes trend determination difficult Gravimetric satellite measurements Use changes in the force of gravity to determine mass Problems: New, untested method Subject to interference from atmosphere and oceans

Results: East Antarctica : 

Results: East Antarctica Largest ice reservoir on earth, smallest range of variability (%) -1 to + 67 Gt year-1 since 1992 Spatial patterns suggest that growth is snowfall driven However, two glaciers are losing mass

Results: West Antarctica : 

Some iced areas are in rapid retreat (loss) Range -47 to -59 Gt year-1 Some data suggesting accelerated losses was derived from less than 5% of the land area Thus, it is unlikely that losses have increased since 1990’s The majority of the Antarctic Peninsula shows snow driven growth Enough to cancel out losses from Larsen A and B shelves The peninsula contribution to sea level rise is negligible Results: West Antarctica > West > East

Results: Greenland : 

Interior (high altitude) growth Exterior (low altitude) loss 1990’s: -50 Gt year-1 Today -120 Gt year-1 Increased mass loss has occurred Decadal change is“probably modest” Results: Greenland

Implications : 

Combined imbalance is -125 Gt year-1 Contribution to sea level: +0.35 mm year-1 Total sea level rise is 3.0 mm year-1 Some glaciers have accelerated 20-100% over the past decade Much uncertainty remains How much do ice streams or buried hydrologic connections contribute? How much is increased meltwater lubricating glaciers? Will contributions remain small? Implications

Remaining Work : 

Basal topography and basal hydrology need to be understood Interactions between ice and surrounding seas needs to be established Mathematical models of glacier dynamics need to be developed Snow forecast models need to be developed using ice core and meteorological data More satellite measurements and more satellites Remaining Work

Questions : 

Why is understanding the ice sheet dynamics important? Why not just measure ocean levels? Hey, why don’t we just pump the meltwater from Greenland to the SW United States and from Antarctica to China? Sounds like a solution to both problems! Questions von Haden et al., 2009

Questions : 

Why do we keep giving these indecisive scientists more money when they can’t even agree on whether or not Antarctica is getting warmer or colder? Imagine how much bottled water we could be buying with that money! Questions Steig et al., 2009 (Nature) NASA, 2004 (Earth Obs.)

Ooops… “A more recent version was published on November 21, 2007. The new version extended the data range through 2007, and was based on a revised analysis that included better inter-calibration among all the satellite records that are part of the time series.” : 

Ooops… “A more recent version was published on November 21, 2007. The new version extended the data range through 2007, and was based on a revised analysis that included better inter-calibration among all the satellite records that are part of the time series.”