Brooks Range, AK Global measurements of atmospheric gases and aerosols Amazon Basin, Arctic Ocean measurements, Steven C. Wofsy and the Science Team of the BARCA Program and the HIAPER Pole-to-Pole Observations Program

Global environmental changes—in the “natural” environment and the built environment— represent some of the most powerful forces that give rise to “extreme” or “sudden” events. This lecture discusses changes in the chemical composition of the atmosphere – what we know about the past, and the present changes that are unfolding.

The temperature of the earth has increased by 0.8 C since

The heavier temperature lines from 160,000 BP to present reflect more data points for this time period, not necessarily greater temperature variability. Climate and Atmospheric History of the past 420,000 years from the Vostok Ice Core, Antarctica, by Petit J.R., Jouzel J., Raynaud D., Barkov N.I., Barnola J.M., Basile I., Bender M., Chappellaz J., Davis J. Delaygue G., Delmotte M. Kotlyakov V.M., Legrand M., Lipenkov V.M., Lorius C., Pépin L., Ritz C., Saltzman E., Stievenard M., Nature, 3 June Paleoclimate data from Antarctic Ice Cores

Changes in atmospheric composition: “Greenhouse gases”, CO 2 Time from present 1000’s of years CO 2 change from the present, ppm

How are people changing the global environment?

Atmospheric methane Atmospheric Methane Concentration (parts per billion) Atmospheric Methane Concentration , , , Time before present (Years) Time before present (Years)

Intergovernmental Panel on Climate Change – IPCC

Insert a news item showing that increasing numbers of the public think "Climate Change" is a hoax, or too uncertain to inform policy, etc.

Some questions about the global environment: Q1. How quickly is the earth warming, and what are the consequences ? (Not required to ask, and answer this question: perfect knowledge of how much warming might be attributed to human activities.) Q2. Is aridity (dryness; Precipitation – Evaporation) increasing in vulnerable places? Q3. What climate changes are ongoing in the Arctic; what is the response of sea level, and of “greenhouse” gases (CO 2, CH 4 )?  Examples of recent studies of the Arctic environment

Changes in Sea Level are linked to climate through the temperature of the ocean and the stranded ice on the continents

Rate of Ice volume change: All Greenland: -238 km 3 /yr South Greenland: -164 North Greenland: N -238 km 3 /yr = 0.5 mm/yr sea level rise

The Arctic Ocean has been covered by floating ice for all human history… …until What do these changes mean for climate, forests, crops? 1. Arctic

GV launch in the rain, Anchorage, January, 2009 (HIPPO-1) HIPPO platform: NCAR Gulfstream V "HIAPER"

41+ kft 28 kft Flight Plan across the arctic ocean 60N to 82N, August 2011

Photos: S. Wofsy August, 2011

UT NN GGLAT GGLON ALT m T o C UT NN GGLAT GGLON ALT m T o C UT NN GGLAT GGLON ALT m T o C UT NN GGLAT GGLON ALT m T o C Photos from 19 Aug 2011

Photos: S. Wofsy Mist rising from very warm water 200km in the ocean

CH 4 in the arctic atmosphere

GLOBAL METHANE SOURCES, Tg a -1 [IPCC, 2007] ANIMALS LANDFILLS GAS COAL RICE TERMITES WETLANDS BIOMASS BURNING Sink: oxidation by OH (lifetime of 10 years)

CH 4 HIPPO Methane is being produced in the surface waters of the Arctic Ocean, especially where the ice pack has broken up, and we see this new emission in the atmosphere.

Slide from: E. A. Kort Relationships between tracers with distinct sources: A tool for understanding large scale sources and sinks of GHGs.

82N 15 April 2010 CO 2 78N 02 Nov ppm CH 4 CH 4 :CO 2 =.0085

Photos: by; B. C. Daube & J. V. Pittman

Summary: The Arctic The data show: Dense pollution at both very high altitudes, and at low levels, in the Arctic. Sources of CH 4 in the Arctic from from the ocean surface, significant compared to fossil fuel extraction and land surface. Extensive loss of floating ice in the Arctic Ocean, and melting of glacial ice on Greenland. … and a lot more

Summary: Environmental Science and Engineering, Global Change element What people in this field are doing: Making measurements in the atmosphere, in the sea, on land, and in the ecosystems of land an sea. Creating databases that can be accessed widely, and constructing models to simulate natural systems. Analyzing and modeling these observations to address questions important to science, and to society. … and a lot more