gamma radiation, 439, 439f

Garamba National Park, 239f, 241f

garbage patches, 120–121, 123–124

Garbers, Bernd, 453, 464

Garrity, Michael, 461

gender bias, 75f

one-child policy and, 75

gendercide, 75

gender composition of population, 73–75

gene frequencies, 202

I-10

Gene Revolution, 305–309

genes, 202

genetically modified (GM) crops, 305–309

cross-pollination and, 309

genetically modified organisms (GMOs), 306

concerns about, 309–310

food free of, 308f

making, 307f

proponents of, 310

trade-offs of, 311f

types and examples of, 309t

genetic diversity, 162, 225, 226f

evolution and, 202–206

genetic drift, 208, 209f

genetic mutation, 204

geology

Earth’s composition, A–12

Earth’s crust, A–13

geothermal energy, 458–460

harnessing, 459f

geothermal heating system, residential, 460f

geothermal heat pumps, 458–459

geothermal power plants, 458–459

glaciers, 411

Global Burden of Disease, 277

Global Canopy Programme, 157

Global Mercury Assessment, 350

global warming, 405. See also climate change

GM crops. See genetically modified crops

GMOs. See genetically modified organisms

Goldstein, Miriam, 128

GoodGuide, 117

GoogleGuide app, 115

Gower, Claire, 169

Grand Coulee Dam, 460–461, 464f

graphing

area graphs, A–9

bar graphs, A–8

line graphs, A–4–A–6

pie charts, A–7

scatter plots, A–7

grazing, rotation method, 326f

“Great Atlantic Garbage Patch,” size of, 120–121, 123–124

“Great Pacific Garbage Patch,” 120, 124

Green alleys, 292, 294f

Greenbelt Movement, 19

green building, 504, 506f

green business, 111–112

green cities, 509

Greenhalgh, Susan, 69

Just One Child: Science and Policy in Deng’s China, 67

greenhouse effect, 407, 410

greenhouse gases, 407, 410

cap-and-trade, 472

curbing emissions of, 422

emission credits, 485f

Kyoto Protocol and regulation of, 483

nuclear energy and reducing, 436

regulation of, 473

U.S. and emissions of, 484

Greenland Ice Sheet, 412f

Greenland Vikings, 3f

Brattahlid, Greenland, 13f

climate change and, 7–8

diet of, 8–9, 13

disappearance of, 4–6

environmental damage and, 8

Hvalsey, Greenland, 3f

Inuit and, 9

settlement, 4f

unwillingness to change, 13

Green Revolution, 303, 334

perks and problems of, 304f

Green Revolution 2.0, 308

green roofing, 506–507

green taxes, 397, 479

greenwashing, 114

of food, 332

Griffin, Kevin, 146, 154, 155

Grimes, Robin, 445

gross primary productivity, definition, 182

ground-level ozone, 26, 385, 390t

levels of, 401

ground-source heat pump, 458–459

groundwater, 262–263, 265f

GWRS, 260, 261f, 274–275, 274f

saltwater intrusion and, 265

growth factors

definition, 164

population size and, 171f

growth rate, 64

Guam, 201f

brown tree snake on, 200, 205–206

endangered birds on, 207f

extinct birds on, 207f

missing birds of, 198–214

native birds on, 201–202

small mammals on, 210

Guam rail (Rallus owstoni), 207f, 208f

“Guinea Worm Cease Fire,” 91

Guinea worm disease (GWD), 80–97

copepods, 89

eradication of, 84, 94f

eradication programs, 90f

filtering water and, 84

human behavior and, 84

infection, 90f

in Nigeria, 82, 94

pipe filters for, 83f

in Sudan, 90–91

transmission, 89

Gulf of Mexico, 278f

Deepwater Horizon oil spill and, 368

hypoxic zone in, 288, 292, 293f, 294

oxygen levels in, 280

regional ecosystem restoration, 293

watershed, 282f

Gulf of Mexico Watershed Nutrient Task Force, 288

Gunnoe, Maria, 348–349, 348f

GWD. See Guinea worm disease

GWRS. See Orange County Groundwater

Replenishment System gyres, 120

major, 123f