Answer to Question 1
Radiative forcing is the influence a particular factor has on the energy balance of the atmosphere-ocean-land system. The factors can be positive, leading to warming, or negative, leading to cooling, as they affect the energy balance. If the factors change over time, they can lead to change in the climate.
Positive examples include increasing levels of water vapor, carbon dioxide, ozone, methane, nitrous oxide, chlorofluorocarbons, soot, and high-flying clouds.
Negative examples are increasing levels of particulates, sulfate aerosols, low-lying clouds, snow and ice (increases planetary albedo), and ozone depletion and volcanic eruption.
Answer to Question 2
Productive use is the exploitation of ecosystem resources for economic gain. Thus products such as timber and fish (and now, bush meat) are harvested and sold for national or international markets. Consumptive use is when people harvest natural resources in order to provide for their needs for food, shelter, tools, fuel, and clothing. Thus, people are hunting for game, fishing, or gathering fruits and nuts in order to meet their food needs, or else they are gathering natural products like firewood, forage for animals, or wood and palm leaves to construct shelters or to use as traditional medicines.
Selected Hypothalamic and Pituitary Agents
Categories of Infectious Agents
A typical electric cooling fan assembly showing the radiator and related components.
Classification of Antihypertensive Agents
Early 20th century warming
Arctic warming: Drunken trees