Antarctica: Did Robert Scott discover coal (!?) on Antarctica?
Antarctica: Was Antarctica once warm and did dinosaurs live there?
Antarctica:  What is the average number of days the South Pole has no sunlight?
Antarctica:  Why does the South Pole have more dark days than light?
Atmosphere:  As we know, the Earth is spinning from west to east at approximately 500 mph (800 km/h).  Why can't I go up in a helicopter in Tallahassee, FL; hover for four hours and descend in Los Angeles?
Atlantic Ocean: how do we know the ocean is widening and by how much?
Biodiversity:  Which has more biodiversity, rainforests or the ocean?
Blue mountains:  Why do distant mountains look blue?
Cold temperatures: how cold can it get on Earth? In the Solar System?
Cold temperatures:  Why is it colder in the mountains?
Compass, at the poles: What will a compass do when I am standing on the geomagnetic pole near the North Pole? What causes magnetic poles to switch polarity? North becoming south and visa versa?
Core:  Why is the center of the earth hot? Why does it remain hot?
Coriolis force: In the North Hemisphere does water goclockwise down the sink?
Desert driest: What is the driest desert on Earth?
Earth get lighter: The Earth gets heavier each day as meteors land. Does Earth ever lose weight? If not, wouldn't Earth eventually get so heavy her orbit would change?
Earth hemisphere: How many miles away from Earth must you go to see the whole circumference of Earth?
Earthquakes:  Q: In school we learned that primary waves can travel through solids, liquids, and gases. My question is: what would happen if a P-wave was traveling through the ground and it reached a canyon and a bird was in the air when the wave started traveling through the air? Would the bird be affected?
Earthquake City: What city has the most earthquakes in the world?
Ending:  When is the end of the world?
Flat Earthers: Which person or group is given credit thinking that Earth is flat?
Geodes:  How are geodes formed?
Global-warming:  Is global warming true?
Hawaii's Hot Islands: what is the source of heat and lava on the Big Island of Hawaii?
Horizon:  If I am on the ground, how many miles away is the horizon?
Hot temperatures:  Where is the hottest place on Earth?  What, if any, humans live there and how do they eke out a living?
Lava and ice: How hot is lava? Can lava be stored? What happens when lava hits ice?
Lightning:  Where in the world do the most lightning strikes occur?
Magnetic poles: The Earth's magnetic poles switch about every 200,000 years. When the poles switch, space radiation that reaches Earth increases. What is the effect on life?
Mass:  How much does Earth weigh and how are you able to come up with that answer without having our planet on a scale???
Meanders:  Why are rivers crooked?
Meanders:  Why are river meanders shallower on the inside and deeper on the outside?
Mount Everest:  What is the temperature of Mount Everest?
Mount Everest:  Mount Everest is so tall it actually touches what?
Mount Everest:  What is the plume often seen trailing from the downwind side of Mount Everest?
Navigation:  When men first sought to reach the north and south poles, with the instruments they had at the time — a sextant, a compass and knowledge of the sun and stars — how did they know when they had reached the poles?
Oxbow lakes: How are oxbow lakes formed?
Poles:  What is the distance from the center of the earth to the North and South Poles?
Recycled:  Does earth get heavier because the human population keeps increasing and the number of living things on earth keeps getting larger? If not, why not?
River meanders: why do rivers, like the Rio Grande and especially the Goosenecks of the San Juan River, meander?
Rocks and Geology: how do rocks weather, what are some good geology books?
Rocks: how to identify rocks
Seiche: What is a seiche? Do it have something to do with tsunamis?
Spin:  How fast does the world spin on its axis?
Tsunami! why is the water pulled out of bays and beach fronts as a tsunami approaches?
Tsunami, highest: What is the highest tsunami ever recorded?
Tsunami, rivers and lakes: Can a local tsunami occur in rivers or in small lakes (like the Dead Sea or Lake Tiberias)?
Twilight:  Why does Phoenix have almost no twilight compared to that back home in Indiana?
Twilight:  All of my life I've heard of the long twilights in the "north" — referring to places like New York — and "no twilight" in the tropics. Yet when I looked up figures I didn’t find much difference between the equator (23 minutes) and a place as far north as Indianapolis (33 minutes). Why so little difference?
Winds:  Two identical aircraft leave from the same point along the equator, at the same time, flying the same speed, one heading east, one west. Which plane will arrive at its origin first? Will the rotation of the Earth affect it? What would happen if the jet stream part of the equation is eliminated?