| NATS 101 Lecture 3 Climate and Weather |
| Climate and Weather |
| ÒClimate is what you expect. | |
| Weather is what you get.Ó | |
| -Robert A. Heinlein |
| Weather |
| Weather – The state of the atmosphere: | |
| for a specific place | |
| at a particular time | |
| Weather Elements | |
| 1) Temperature | |
| 2) Pressure | |
| 3) Humidity | |
| 4) Wind | |
| 5) Visibility | |
| 6) Clouds | |
| 7) Significant Weather |
| Surface Station Model |
| Temperatures | |
| Plotted ¡F in U.S. | |
| Sea Level Pressure | |
| Leading 10 or 9 is not plotted | |
| Examples: | |
| 1013.8 plotted as 138 | |
| 998.7 plotted as 987 | |
| 1036.0 plotted as 360 |
| Sky Cover and Weather Symbols |
| Wind Barbs |
| Direction | |
| Wind is going towards | |
| Westerly Þ from the West | |
| Speed (accumulated) | |
| Each flag is 50 knots | |
| Each full barb is 10 knots | |
| Each half barb is 5 knots |
| Slide 7 |
| Practice Surface Station |
| Temperate (oF) | |
| Pressure (mb) Last Three Digits (tens, ones, tenths) | |
| Dew Point (later) Moisture | |
| Wind Barb Direction and Speed | |
| Cloud Cover Tenths total coverage |
| Practice Surface Station |
| Sea Level Pressure | |
| Leading 10 or 9 is not plotted | |
| Examples: | |
| 1013.8 plotted as 138 | |
| 998.7 plotted as 987 | |
| 1036.0 plotted as 360 | |
| Surface Map Symbols |
| Fronts | |
| Mark the boundary between different air massesÉlater | |
| Significant weather occurs near fronts | |
| Current US Map |
| Slide 11 |
| Radiosonde |
| Weather balloons, or radiosondes, sample atmospheric to 10 mb. | |
| They measure temperature moisture pressure | |
| They are tracked to get winds |
| Radiosonde Distribution |
| Radiosondes released at 0000 and at 1200 GMT for a global network of stations. | |
| Large gaps in network over oceans and in less affluent nations. | |
| Stations ~400 km apart over North America |
| Radiosonde for Tucson |
| Example of data taken by weather balloon released over Tucson | |
| Temperature (red) | |
| Moisture (green) | |
| Winds (white) | |
| Note variations of all fields with height | |
| UA Tucson 1200 RAOB |
| Climate |
| Climate - Average weather and range of weather, computed over many years. | |
| Whole year (mean annual precipitation for Tucson, 1970-present) | |
| Season (Winter: Dec-Jan-Feb) | |
| Month (January rainfall in Tucson) | |
| Date (Average, record high and low temperatures for Jan 1 in Tucson) |
| Slide 16 |
| Slide 17 |
| Climate of Tucson Monthly Averages |
| Slide 19 |
| Climate of Tucson Probability of Last Freeze |
| Climate of Tucson Probability of Rain |
| Climate of Tucson Extreme Rainfall |
| Climate of Tucson Snow! |
| Summary |
| Weather - atmospheric conditions at specific time and place | |
| Weather Maps Þ Instantaneous Values | |
| Climate - average weather and the range of extremes compiled over many years | |
| Statistical Quantities Þ Expected Values | |
| Reading Assignment |
| Ahrens | |
| Pages 25-30 | |
| Problems 2.1-2.4 | |
| (2.1 Þ Chapter 2, Problem 1) | |
| DonÕt Forgot the 4Óx 6Ó Index CardsÉ |