Nature & Weather on Facts

What does the Fujita scale measure?

Thu, 05 Nov 2026 19:12:18 +0000

Why damage, not wind?

Tornado winds are very hard to measure directly; they often destroy instruments in their path. So experts survey the damage afterward and estimate the winds needed to cause it.

What is the Gulf Stream?

Thu, 05 Nov 2026 19:11:12 +0000

A river in the ocean


Speed	Up to about 2.5 m/s (5.6 mph) near Florida
Width	About 100 km
Flow	Many times the combined flow of all the world’s rivers
Water temperature	Often 5–10°C warmer than the surrounding sea

How it warms Europe

London is farther north than Calgary, Canada, yet London’s winters are much milder. Warm water carried north releases heat into the air, and the westerly winds blow that milder air over Europe. Scientists note that weather patterns and the wind itself also play big roles, but ocean heat is an important part.

What is the largest rainforest in the world?

Thu, 05 Nov 2026 19:10:44 +0000

Amazon in numbers


Forest area	~5.5 million km²
Countries	Brazil, Peru, Colombia, Venezuela, Ecuador, Bolivia, Guyana, Suriname, French Guiana (France)
Trees	An estimated 390 billion of about 16,000 species
Indigenous peoples	Hundreds of groups, including some with no regular outside contact

The Amazon River

The Amazon River carries more water than any other river, about 20% of all the fresh water that rivers pour into the world’s oceans. It’s around 6,400 km long, close to the Nile. Its mouth is so wide that it has an island, Marajó, about the size of Switzerland.

What type of cloud causes thunderstorms?

Thu, 05 Nov 2026 19:10:16 +0000

The name comes from Latin: cumulus means “heap” and nimbus means “rain cloud.” A cumulonimbus is literally a heaped-up rain cloud.

How a thunderstorm cloud forms

Warm, moist air rises, often on hot afternoons.
As it rises, it cools, and water vapor condenses into a puffy cumulus cloud.
If the air keeps rising strongly, the cloud grows taller and taller.
Near the top, it hits the stratosphere, where it can’t rise further, so it spreads out into a flat anvil.
Ice and water particles collide inside, building up electric charge that releases as lightning.

The 10 main cloud types

Height	Cloud types
High (above ~6 km)	Cirrus, cirrocumulus, cirrostratus
Middle (2–6 km)	Altocumulus, altostratus
Low (below 2 km)	Stratus, stratocumulus, nimbostratus
Vertical (spanning levels)	Cumulus, cumulonimbus

Thunderstorm safety

If you can hear thunder, you’re close enough to be struck by lightning.
Go indoors or into a hard-topped car.
Avoid open fields, hilltops, tall isolated trees and water.
Wait about 30 minutes after the last thunder before going back outside.

Counting the distance

Light travels almost instantly, but sound travels about 1 km every 3 seconds (1 mile every 5 seconds). Count the seconds between a flash and its thunder to estimate how far away the storm is.

What is the largest coral reef in the world?

Thu, 05 Nov 2026 19:10:06 +0000

What is a coral reef?

Corals look like rocks or plants, but they’re animals: colonies of tiny creatures called polyps. Each polyp builds a hard limestone skeleton. Over thousands of years, these skeletons pile up into reefs. Corals get much of their food and color from tiny algae living inside them.

What is the deepest lake in the United States?

Thu, 05 Nov 2026 18:34:19 +0000

The deepest US lakes

Rank	Lake	State	Max depth
1	Crater Lake	Oregon	~1,949 ft (594 m)
2	Lake Tahoe	California/Nevada	~1,645 ft (501 m)
3	Lake Chelan	Washington	~1,486 ft (453 m)
4	Lake Superior	Michigan/Minnesota/Wisconsin (and Canada)	~1,333 ft (406 m)
5	Lake Pend Oreille	Idaho	~1,150 ft (350 m)

Crater Lake is also one of the deepest lakes in the world, often ranked around ninth or tenth.

What is the largest national park in the US?

Thu, 05 Nov 2026 18:33:28 +0000

The 5 largest US national parks

Rank	Park	State	Size
1	Wrangell–St. Elias	Alaska	~13.2 million acres
2	Gates of the Arctic	Alaska	~8.5 million acres
3	Denali	Alaska	~6.1 million acres
4	Katmai	Alaska	~4.1 million acres
5	Death Valley	California, Nevada	~3.4 million acres

Sizes include the parks’ preserves. Death Valley is the largest park in the contiguous (lower 48) United States.

Why is the ocean important?

Thu, 05 Nov 2026 17:47:25 +0000

By the numbers

~71%: Share of Earth’s surface covered by ocean
~50%: Estimated share of Earth’s oxygen produced by ocean plankton and plants
90%+: Share of the extra heat from global warming absorbed by the ocean
~25%: Rough share of human CO₂ emissions absorbed by the ocean each year

Five reasons the ocean matters

1. Oxygen. Tiny drifting plants called phytoplankton photosynthesize like trees on land. Together with seaweed and other ocean plants, they produce roughly half of the oxygen on Earth.

Why is biodiversity important?

Thu, 05 Nov 2026 17:47:16 +0000

What biodiversity means

Biodiversity works at three levels:

Level	Meaning	Example
Genetic	Variety within a species	Thousands of rice varieties, some resistant to drought
Species	Variety of different species	Bees, birds, fungi, trees and microbes in one forest
Ecosystem	Variety of habitats	Rainforests, coral reefs, wetlands, grasslands

Six reasons it matters

Food: A large share of the world’s main food crops benefit from animal pollination, mostly by insects. Healthy soil depends on billions of tiny organisms.
Clean water and air: Wetlands filter water; forests and ocean plankton produce oxygen and store carbon.
Medicine: Many medicines come from or were inspired by nature, such as aspirin from willow bark and penicillin from mold.
Resilience: Varied ecosystems cope better with pests, disease and extreme weather, like a portfolio that isn’t invested in just one stock.
Climate: Forests, peatlands and oceans absorb huge amounts of carbon dioxide.
Culture and wellbeing: Nature supports tourism, livelihoods, traditions and mental health.

What threatens it

Scientists point to five main drivers of biodiversity loss:

What is the polar vortex?

Thu, 05 Nov 2026 17:25:53 +0000

The polar vortex isn’t a storm that suddenly appears. It’s a permanent feature of the atmosphere that strengthens in winter and weakens in summer. News headlines tend to mention it when something unusual happens to it.