Monitoring Earth’s Climate System Current Weather Climate Change Discussion The Climate System Climatic Anomalies and Feedback Loops Observing the Climate System Remote Sensing by Satellite International Cooperation Modeling Earth’s Climate System For Next Class: Read Chapter 2 (pp. 50-66)

Homework Discussion (a) Is the climate changing? On what evidence? (b) Do people have anything to do with climate change? How? (c) Should we care about climate change? Why? (d) Can we do anything about climate change? If so, what? (e) Is it worth doing anything about it? If so, why?

The Climate System Atmosphere Relatively thin envelope of gases and tiny suspended particles surrounding the planet Divided into four layers: Troposphere Stratosphere Mesosphere Thermosphere © AMS

What is the Cryosphere and what are some of its components?

What is the Cryosphere? Consists of various forms of frozen water at the planet’s surface.

Photo credit: D.K. Hall / NASA

Components of the Cryosphere Snow – a collection of loosely bonded ice crystals deposited from the atmosphere. Sea ice – any form of ice found at sea which has originated from the freezing of sea water. Glaciers – fallen snow that, over many years, compresses into large, thickened ice masses that move. Ice Sheet – mass of glacial land ice extending more than 50,000 square kilometers (20,000 square miles). The Greenland and Antarctic Ice Sheets are the only two that currently exist.

Ice Shelves – thick slab of ice, attached to a coastline and extending out over the ocean as a seaward extension of an ice sheet or series of glaciers. Iceberg – massive piece of ice of greatly varying shape, protruding 5 m or more above sea-level, which has broken away from a glacier and which may be afloat or aground.

Ch. 2 Driving Question How do climate scientists investigate the spatial and temporal characteristics of climate, climate variability and climate change? © AMS

Climatic Anomalies Departures from the long-term average Do not occur with the same sign or magnitude everywhere Positive anomalies: above long-term averages Negative anomalies: below long-term averages © AMS

Climatic Anomalies Positive feedback example Negative feedback example © AMS

Observing the Climate System In Situ Measurement Radiosonde: small instrument package equipped with a radio transmitter that is carried aloft by a balloon Create soundings, or altitude readings of temperature, air pressure and dewpoint Launched at 12 hour intervals at ground stations world wide © AMS

© AMS

Radiosonde Release in Peru https://www.youtube.com/watch?v=J_6iQkwF9KA

Observing the Climate System In Situ Measurement Ships, buoys, floats, gliders, piloted submersibles, autonomous instrumented platforms and vehicles, and undersea observatories provide in situ ocean data © AMS

Argo floats obtain profiles of temperature and salinity in the ocean Sample plots of float-derived temperature and salinity profiles © AMS

Observing the Climate System Remote Sensing by Satellite Electromagnetic radiation: both a form of energy and a means of energy transfer, travel as waves Electromagnetic spectrum: composed of different forms of radiation © AMS

Observing the Climate System Remote Sensing by Satellite Satellites fly in either geostationary or polar orbits Geostationary orbit Polar orbit © AMS

Observing the Climate System Visible Satellite Image © AMS

Observing the Climate System Infrared Satellite Image © AMS

Questions? Take out a sheet of paper and write down any questions about the material we covered in lecture today.