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What’s the difference between weather and climate?
Get out your notebooks, get your pencil sharpened, be ready to go when the bell rings. Climate Change April 17 What’s the evidence? What’s the cause? What’s the difference between weather and climate?
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You will need some colored pencils or crayons or highlighters: yellow, orange, red, blue
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Earth's average temperature has increased about 2 degrees Celsius during the 20th century. What's the big deal? Two degrees may sound like a small amount, but it's an unusual event in our planet's recent history. Earth's climate record, preserved in tree rings, ice cores, and coral reefs, shows that the global average temperature is stable over long periods of time. Furthermore, small changes in temperature correspond to enormous changes in the environment. For example, at the end of the last ice age, when the Northeast United States was covered by more than 3,000 feet of ice, average temperatures were only 5 to 9 degrees cooler than today.
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What’s the difference between weather and climate?
Sort the word cards into 2 categories.
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What’s the difference in weather and climate?
The day-to-day changes in temperature Hard to predict for more than a few days ahead Can change rapidly and unpredictably Average temperature over a very long period of time Predictable Doesn’t change much at all Ice core samples indicate the climate of the earth hasn’t changed much overall, except recently…
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https://climate.nasa.gov/interactives/climate-time-machine
Go to this website to see how things have changed over time…
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1. Longer, frost-free growing season This is a beneficial impact to global warming.
The largest increases in the frost-free season (more than eight weeks) are projected for the western U.S., particularly in high elevation and coastal areas. The increases will be considerably smaller if heat-trapping gas emissions are reduced.
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2. Precipitation Patterns Will Change
Increases in precipitation that are greater than the the overall average rainfall will create more flooding in the Northern US. More winter and spring precipitation is projected for the northern United States, and less for the Southwest, over this century.
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3. More Droughts and Heat Waves
Droughts in the Southwest and heat waves (periods of abnormally hot weather lasting days to weeks) everywhere are projected to become more intense, and cold waves less intense everywhere. Summer temperatures are projected to continue rising, and a reduction of soil moisture, which exacerbates heat waves, is projected for much of the western and central U.S. in summer. By the end of this century, what have been once-in-20-year extreme heat days (one-day events) are projected to occur every two or three years over most of the nation.
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4. Hurricanes will become stronger, more intense, and more frequent
The intensity, frequency and duration of North Atlantic hurricanes, as well as the frequency of the strongest (Category 4 and 5) hurricanes, have all increased since the early 1980s. The relative contributions of human and natural causes to these increases are still uncertain. Hurricane-associated storm intensity and rainfall rates are projected to increase as the climate continues to warm.
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5. Arctic Ice Disappears The Arctic Ocean is expected to become essentially ice free in summer before mid-century.
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Our Oceans are becoming more Acidic
Excess carbon absorbed by the ocean threatens to turn coral reefs, one of the most diverse and important ecosystems on Earth, into ghostly bleached wastelands. "The ocean surface acts like a sponge to soak up excess carbon dioxide from the atmosphere," says Scott Doney, a senior scientist in marine chemistry at the Woods Hole Oceanographic Institution in Woods Hole, Mass. Much of the extra dissolved carbon is in the ocean's upper few thousand feet. However, at high latitudes, surface water quickly cools, becomes saltier and denser and sinks, carrying the dissolved carbon to some of the deepest parts of the ocean.
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Since most corals live in shallow waters, coral reefs, some of the most biologically diverse places on Earth, are particularly vulnerable. "They are already under assault from warming water, over-fishing and habitat degradation," says Doney. "Environmental stress is leading to more incidents of ‘coral bleaching,' which occurs when the symbiotic algae that lives inside the coral leaves or dies, and from which reefs often do not recover. Ocean acidification may push corals over the edge."
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