08 - 3/3/2008 How do we measure CO2 and how does it effect...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
3/3/2008 1 How do we measure CO 2 and how does it effect the climate? The atmosphere is really thin! Weather vs. Climate There is a difference!! Weather is the day to day changes in variables such as cloud cover, temperature, wind speed/direction, humidity Very UNPREDICTABLE beyond several days! Climate is the long-term average of particular variables. PREDICTABLE! Weather Climate Today is a cold day. Winter is colder than summer. The wind is blowing from the southwest today. Winds generally blow west to east across mid-latitudes. It may rain tomorrow. There are wet seasons and dry seasons in many parts of the world. It will get colder overnight, then warm up again tomorrow. There have been many glacial and interglacial periods. Today’s temperature is 30 degrees F. Over the past 100 years, the average global temperature has risen. Earth’s Radiation Balance Incoming energy = Outgoing energy Incoming energy is sun“light” (but not just the light we see!) Outgoing energy is earth’s radiation (mostly in the infrared (IR)) http://www.ldeo.columbia.edu/edu/dees/V1003/images/wavelengths.gif What happened here? SW flux anomaly = changes in albedo, or how reflective the earth looks from space. When we change the composition of the atmosphere, we change the energy balance! From the IPCC WG1 AR4
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3/3/2008 2 What is a Greenhouse Gas? A greenhouse gas is a molecule that absorbs and re- emits radiation at the wavelength(s) emitted by the earth (in the IR band). Include: Carbon Dioxide (CO 2 ) (what I study, in the news the most) Methane (CH 4 ) (more potent, but there is less of it) Water Vapor (H 2 O) (highest concentration, but also highly variable) Ozone (O 3 ) (good in the upper atmosphere, bad in the lower atmosphere) ht p:/ www.solcomhouse.com/globalwarming.htm When these molecules absorb radiation from the earth, they can stretch, vibrate, rotate faster, etc. ht p:/ www.windows.ucar.edu/physical_science/chemistry
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/29/2008 for the course EAS 104 taught by Professor Brown during the Spring '08 term at Purdue University-West Lafayette.

Page1 / 6

08 - 3/3/2008 How do we measure CO2 and how does it effect...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online