Across
- 4. -the amount that the population would grow if there were unlimited resources in its environment.
- 5. -process in which there is an increase in the number of people living and working in a city or metropolitan area.
- 8. -any of the almost spherical concentric regions of matter that make up the earth and its atmosphere, as the lithosphere and hydrosphere.
- 10. -is a coupled ocean-atmosphere phenomenon that is the colder counterpart of El Niño, as part of the broader El Niño–Southern Oscillation climate pattern.
- 12. -(of a substance or object) capable of being decomposed by bacteria or other living organisms.
- 13. -the regions of the surface, atmosphere, and hydrosphere of the earth (or analogous parts of other planets) occupied by living organisms.
- 16. factor A limiting factor is anything that constrains a population's size and slows or stops it from growing.
- 17. -is a highly reactive gas composed of three oxygen atoms. It is both a natural and a man-made product that occurs in the Earth's upper atmosphere.
- 18. is ecological succession that begins in essentially lifeless areas, such as regions in which there is no soil or where the soil is incapable of sustaining life (because of recent lava flows, newly formed sand dunes, or rocks left from a retreating glacier).
- 23. rate The fertility rate at a given age is the number of children born alive to women of that age during the year as a proportion of the average annual population of women of the same age.
- 24. -all the inhabitants of a particular town, area, or country.
Down
- 1. -a substance that pollutes something, especially water or the atmosphere.
- 2. rate -the ratio of deaths to the population of a particular area or during a particular period of time, usually calculated as the number of deaths per one thousand people per year.
- 3. is one of the two types ecological succession of a plant's life. As opposed to the first, primary succession, secondary succession is a process
- 6. -the envelope of gases surrounding the earth or another planet.
- 7. -is air pollution that reduces visibility.
- 9. -means an animal leaves its home because the habitat is no longer ideal for them and they need to find a more suitable environment.
- 11. -is the permanent removal of trees to make room for something besides forest. This can include clearing the land for agriculture or grazing, or using the timber for fuel, construction or manufacturing.
- 14. -means an animal establishes a home in a habitat because it has resources it can utilize or because the habitat is ideal for them.
- 15. -the natural home or environment of an animal, plant, or other organism.
- 19. -the weather conditions prevailing in an area in general or over a long period.
- 20. -an irregularly occurring and complex series of climatic changes affecting the equatorial Pacific region and beyond every few years, characterized by the appearance of unusually warm, nutrient-poor water off northern Peru and Ecuador, typically in late December.
- 21. layer a layer in the earth's stratosphere at an altitude of about 6.2 miles (10 km) containing a high concentration of ozone, which absorbs most of the ultraviolet radiation reaching the earth from the sun.
- 22. warming a gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, chlorofluorocarbons, and other pollutants.
- 25. runoff Urban runoff is surface runoff of rainwater created by urbanization.