Chapter 23

1. Chapter 23 The Heat Is On

2. Heat is ON • Burr Morse’s family maple syrup • One in four trees in Vermont is sugar maple tree. Many collect sap and boil for maple syrup. • Each year the state produces about 1 million gallons of syrup • Last 20 years, bad seasons with temperature a little warm. • Must be cool at night and warm during the day. • Most nights are now not cool enough for syrup production • Morse and others notice a shift in temperature

3. Warm Weather • Warmer winters may have large economic impact on the New England region • Maple industry may become economically untenable during the next 50-100 years • Total impact of maple in Vermont alone is 200 million per year. • Before 1900, 80% of world’s maple system came from trees in US, now reversed with Canada out-producing US- Canada now 80%

4. Changes in Climate Can Have Economic Impacts • Climate change can shorten or lengthen the growing season of crops and therefore affect the livelihoods of area farmers.

5. Climate Change • Climate change is a natural part of the environment, but scientists are finding evidence that humans are accelerating the pace of change.

6. Rising Temperatures Affect Plant Behavior • For many species, temperature cues seasonally appropriate tasks such as mating or producing flowers in the springtime. Rising temperatures interfere with these natural rhythms.

7. Rising Temperatures Affect Plant Behavior • An ecosystem is a complex, interwoven system of interacting components. It includes both the community of living organisms present in an area and features of the nonliving environment. (soil, water, air)

8. Rising Temperatures Affect Plant Behavior • A change in one part of an ecosystem may upset other parts of the ecosystem. • Because the biotic and abiotic parts of an ecosystem can and do change, ecosystems are not static entities. • They are dynamic systems.

10. Rising Temperatures Affect Plant Behavior • What will happened if the climate changes so much that New England no longer provides a suitable habitat for maple trees • Ahabitatis the physical environment where an organism lives and to which it is adapted. • Scientists predict the New England forest will resemble Virginia and Tennessee at the end of the century

11. Biomes • Forest are biomes • A biome is a large geographic area defined by its characteristic plant life, which in turn is determined by temperature and levels of moisture. • Climate change is beginning to alter the boundaries and plant composition of some biomes.

13. Biomes • Deserts are characterized by extreme dryness. Cold deserts experience cold winters and hot summers, while hot deserts are uniformly warm throughout the year.

14. Biomes • Coniferous forests are characterized by evergreen trees, with long and cold winters and only short summers.

15. Biomes • Tundra are characterized by low-growing vegetation and a layer of permafrost (frozen all year long) very close to the surface of the soil.

16. Biomes • Temperate deciduous forests are characterized by trees that drop their leaves in winter. Winters are much colder than summers in temperate deciduous forests.

17. Biomes • Tropical forests are characterized by warm temperatures and sufficient rainfall to support the growth of trees. Tropical forests may be deciduous or evergreen, depending on the presence or absence of a dry season.

18. Biomes • Grasslands are characterized by perennial grasses and other non-woody plants.

19. Biomes • Marine biomes are aquatic biomes that include the oceans, coral reefs, and estuaries.

20. Biomes • Freshwater biomes are aquatic biomes that are characterized by having a low salt concentration. Freshwater biomes include ponds and lakes, rivers and streams, and wetlands.

21. The Greenhouse Effect • Although temperature swings and shifts in the ranges of organisms are natural phenomena, the amount of warming in recent years is unprecedented, • Evidence suggests that the change is not merely part of a natural cycle.

22. The Greenhouse Effect • From 1880 to 2010, the earth’s surface has warmed about 0.8C (NASA) - significant • Eighteen of the warmest years on record occurred in just the past 20 years • Last decade 2000 – 2010 was hottest so far • Greenhouse effect • Trapping of heat in earth’s atmosphere • Sunlight warm’s the earth’s surface

23. The Greenhouse Effect • As sunlight shines on earth, it warms the earth’s surface. • This heat radiates back to the atmosphere, where it is absorbed by greenhouse gases, CO2, methane, NO • Keeping the atmosphere and surface of the earth warm.

24. The Greenhouse Effect • The greenhouse effect is a natural process that helps maintain life-supporting temperatures on earth. • In recent years, however, rising levels of greenhouse gases have increased the strength of the greenhouse effect. The result is global warming, an overall increase in the earth’s average temperature.

25. Global Warming • Without the greenhouse effect, the average surface temperature of the planet would be rigid (-18C (OF)) • As the amount of greenhouse gases in the atmosphere has increased, so have the temperatures.

27. Temperature and Climate changes • Climate change is happening quickly • So many species on earth are sensitive to climate change • Plants are slower to adapt than animals (Why) • We don’t know what the overall effects will be of the effect of climate change • Predator/prey relationships alters (birds/insects) • Some may benefit

28. Rising Temperatures Result in Ecosystem Change • Climate change is having a dramatic impact on entire ecosystems.

29. Arctic Meltdown • Snow and ice covered regions such as the Arctic stand to suffer most from warming climate. Melting • The Arctic has warmed, on average, twice as much as the rest of the world. • Sea ice both reflects solar radiation and insulates ocean • As global temperatures rise, ice begins to melt. With less sea ice, more solar radiation is absorbed by the ocean and more of the relatively warm ocean is exposed to air, raising the air temperature even more. • More ice lost, temperature will rise at an accelerated pace

30. Arctic Meltdown • Rising temperatures have caused the polar ice cap to melt and break apart earlier in the season. • This reduction in summer sea ice is threatening the survival of polar bears.

31. The Carbon Cycle • Atmospheric carbon dioxide concentrations are higher now than they have been in more than 700,000 years.

32. Our Carbon Footprint • Burning fossil fuels liberates the carbon that was once stored as organic molecules in the earth and releases it into the atmosphere as carbon dioxide gas.

33. Our Carbon Footprint • The cattle that we raise have methane-producing microbes in their guts which help them digest the plant matter they eat.

34. Our Carbon Footprint • Destroying and burning forests liberates carbon that was stored as organic molecules in trees and releases it into the atmosphere as carbon dioxide. In addition, it diminishes the capacity for carbon dioxidecapturing photosynthesis.

35. Our Carbon Footprint • Methane is released from rice paddies because of the methane-producing bacteria that live in the flooded, and therefore anoxic (oxygen-free), soil. Preparing land for growing rice may also destroy forests that formerly stored carbon in organic form.

36. Our Carbon Footprint • The production of concrete results in the release of large amounts of carbon dioxide.

37. The Nitrogen Cycle • Nitrogen atoms cycle between different chemical and biochemical compounds as they move from organisms to the soil, water, and air, and back to organisms.

38. The Phosphorus Cycle • Phosphorus cycles primarily through soil, water, and organisms.