ENVIR ST 260 1st Edition Lecture 10 Outline of Last Lecture I Disturbance Regime a Scale b Frequency c Intensity II Predictability III Responsibility IV Reconstruction Outline of Current Lecture I Notes on Exam II Precipitation and Temperature in Ecosystems III Climate versus Weather IV Measuring Changes in Climate and Weather V Next Week Current Lecture Notes on Exam Essay Questions Talking about the essay questions in discussion will help you get on the right track but you need to think about it beyond just in that class Viruses vs Bacteria These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute A lot of people talked about viruses and bacteria as if they were the same thing The professor tried to give the benefit of the doubt but people still got docked points for that Vaccines are a way to train your body to recognize something that shouldn t be there but they don t actually make you sick they help you build antibodies They don t do you good if you re already sick It s way off base to say a vaccination causes bacteria to mutate Oil Propagation Some people took the first step in saying that they d make more of the bacteria but they didn t explain how which misses the context of the question She was looking for something along the lines of taking a sample of bacteria with that trait and exposing them to oil to select for the trait Vague answers didn t get you points because you needed to explain how you d propagate and touch on artificial selection Short Answer In preparation for the next exam we should remember that these should be short She s not looking for novels If she says to define a term she needs a sentence and not a paragraph If she asks for an example you can make it concise and only two sentences She s worried about time limits so keep this in mind for the next exam Precipitation and Temperature in Ecosystems Clicker Questions Average annual rainfall 40 inches and average annual temperature of 75 degrees Grassland or savanna Average annual rainfall 130 inches and average annual temperature of 75 degrees Tropical rainforest The difference between the tropical rainforest and the savanna is the amount of rainfall the average temperature is the same Average annual rainfall 20 inches and average annual temperature of 14 degrees Tundra Recap Water availability High low temperature tolerance Huge selection pressure These are the really big drivers Whenever we talk about ecosystems we start with precipitation and temperature We should be able to learn to expect what kind of plant and animal communities will be present Evolution of Animals to Suit Environment Polar bears They re present in the arctic They have thick fur large bodies and insulation it s all protection from the cold In order for polar bears to survive in the arctic they had to adopt these traits Desert Mice They re present in arid ecosystems with low rainfall They have smaller body sizes and really efficient kidneys they have modified nasal passages that are really efficient in minimizing water loss Their metabolisms are built on water conservation The animals have adapted to this environment Amphibians They re present in tropical regions They need moist warm places The frogs and toads in more arid environments have traits that suit them to that environment Climate versus Weather Climate variables Precipitation Temperature Humidity Winds and atmospheric pressure Weather variables Climate and weather would essentially be the same if you were to just look at the variables However they are two different things Precipitation Temperature Humidity Winds and atmospheric pressure Video Clip on difference between weather and climate Man walking along the beach with his dog climate is steady and weather is sporadic climate is long term and weather is short term Climate versus Weather Climate Weather Long Term Short term Regional Location specific Predictable Less predictable 10 day forecast always changing Changes slowly compared to weather Changes quickly Measuring Changes in Climate and Weather How can we measure changes in weather Digital records Written records Example of Device in Arctic Measures height of snow pressure solar radiation and temperatures Limitations to these sources In the modern age you can go and look at weather on any given day in the past 30 years basically anywhere in the United States Beyond that it gets sketchier For changes in climate we need different sources Measuring Changes in Climate Ice Core Video Clip Collecting climate data through ice cores They re just melting ice which seems really simple but they collect massive quantities of data including levels of CO2 volcanic eruptions conductivity wind speed and direction How accurate is a study like this What are limitations There s potential of contaminating something It only tells you what was happening in the arctic Video Clip Tree Rings They tested red woods because they are fire and disease resistant and are some of the oldest trees They can live to be 2 000 years old In the Pacific North West there is fog so the isotopes are really stable Could you get equivalent data from the tropics No because you get really distinct growth rings in the Pacific North West because it gets cold in the winter and the trees stop growing but in the tropics they re basically growing year round When you look at data sets together you can get an idea of the global climate Next Week Human impacts Test prep Review Chapters 6 11 12 and 13