posted on Jun, 13 2014 @ 07:25 PM
Better yet, Taj, because things are so wonky for me lately, here ya go:
What would the world be like if the land masses were spread out the same way as now - only rotated by an angle of 90 degrees?
It would profoundly alter our biosphere in general and public radio in particular.
Socke asks what would happen if the Earth’s surface were slid around by 90 degrees, putting our current North and South Poles on the equator.
We’re not changing the tilt of the Earth’s axis; we’re just imagining that the surface were arranged differently.
a diagram showing the new location of the equator and the poles
We’ll pick the Greenwich meridian for our new equator, putting the new North and South poles in the Indian ocean (0N, 90E) and off the coast of
Ecuador (0N, 90W). India, Indonesia, and Ecuador would become polar, while Europe, Antarctica, and Alaska would become tropical.
Where would the deserts and forests be? What areas would get better or worse?
This stuff is complicated. In a moment, we'll start using wild speculation to reshape the face of the planet. But first, a brief story to illustrate
just how mind-bogglingly complicated this stuff is:
In Chad, on the southern outskirts of the Sahara, there’s valley called the Bodélé Depression. It was once a lakebed, and the dry dust in the
valley floor is full of nutrient-rich matter from the microorganisms that lived there.
From October to March, winds coming in from the east are pinched between two mountain ranges. When the surface winds climb over 20 mph, they start
picking up dust from the valley. This dust is blown westward, all the way across Africa, and out over the Atlantic.
That dirt—from one small valley in Chad—supplies over 50% of the nutrient-rich dust that helps fertilize the Amazon rainforest.
At least, according to that one study. But if it's right, it wouldn’t be a crazy anomaly. This kind of complexity is found everywhere. The basic
building blocks of our world are crazy.
This is why we can be so certain about large-scale patterns like global warming, where we understand the overall physics pretty well—energy comes
in, less energy goes out, so the average temperature rises—but have a harder time predicting how it will affect any particular place or specific
So even if I were a climate expert—which I’m definitely not—there’d be no way to answer this question with certainty. There are just too many
variables. Instead, think of what follows as a rough sketch of some of the things this alternate Earth could contain.
To start, here’s a map of our reshuffled world:
a map of the reshuffled earth, with asia, africa, and most of antarctica north of the equator and north and south america south of it.
(An equirectangular projection, by the way. This type of equirectangular projection, centered on a north-south meridian instead of the equator, is
specifically called a Cassini projection, so a good name for our alternate Earth might be "Cassini".)
Let’s imagine that this alternate Earth develops over millions of years, with ecosystems and climate zones settling out. Then one day we wake up to
find our current civilization has been magically transported there—cities and all. What would they find?
The climate on the rotated Earth would depend heavily on the details of ocean and atmospheric heat circulation. We'll guess at some of that, but for
now, let's assume this world has extremes which are similar to ours.
So let's add some ice and permafrost near the poles and in mountainous areas:
a map showing ice near the poles and mountainouse areas, shown with a light blue color
Next, we should fill in some green areas and deserts. The locations of these depend heavily on rainfall, so we’ll need to sketch out some winds.
The main driver of our weather is the sun, which heats air near the equator more than at the poles. Hot air rises at the equator and then flows
poleward, and cooler air moves in across the surface toward the equator. This circulation is called a Hadley cell.
illustration of a hadley cell
Hadley cells shift north and south of the Equator with the seasons. At this time of year on our Earth, the sun is directly overhead at about 10°N,
which is why hurricanes are forming near that latitude right now.
Because of the Coriolis effect, the surface winds in a Hadley cell flow from east to west. Further north, for most of the temperate zones, the
prevailing surface winds are west to east. (At times, there are also east-to-west winds circulating around the poles.)
So let’s fill in some wind patterns—keeping in mind that in reality things would be further complicated by land interactions and the location of
persistent high and low pressure systems.
a map with the new wind patterns
Sinking air is cool and dry, so land under the outer edges of the Hadley cells tends to be arid. These regions, lying a bit poleward of 30 degrees,
are known as the horse latitudes.
map showing air movement with horse latitudes labeled
The rising air at the equator carries moisture from the ocean, which then condenses into rain, so tropical areas are usually wet and thick with
growth. Areas near the equator are sometimes dominated by a seasonal monsoon cycle.
In temperate zones, things are more variable. Weather there is dominated by the movement of jet streams and fronts, and depends heavily on geography.
Most of the United States is in this type of region.
With all that in mind, let’s fill in some arid and lush areas:
the same map filled in with various lush (green) and arid (yellow) areas
(Climates can be hard to predict—for example, in our world, Somalia and French Guiana both sit on the equator, at the eastern coast of a continent,
and seem like they should both receive a tropical sea breeze. But coastal French Guiana is dense rain forest while coastal Somalia is an arid desert.
The explanation involves the monsoon cycle.)
And just for fun, here’s a wild guess as to where the hurricane basins would be:
the same map with swaths of red to show where hurricanes might occur
Let’s take a closer look at each continent.
North America has a range of climates similar to what it had before, but flipped north-south. The Arctic Canadian provinces are now tropical, while
Central America is icy and polar. Hurricanes threaten Greenland, Baffin Island, and the Maritimes. Tropical moisture from Baffin Bay and the northwest
(formerly north) Atlantic mixes with cool air flowing down through the US from the Rockies, creating a new Tornado Alley in the prairies inland from
South America looks sort of like the old Europe. It's cool and temperate along the Brazilian coast, with boreal forests and grasslands across much of
its width. In the south, the boreal vegetation gives way to polar tundra, and eventually to the massive icebound Andes, which cut the continent off
from the frozen polar waters. The Amazon, which in our world carries more water than the next seven largest rivers put together, is reduced to
something akin to the Mississippi.
Asia is flipped in the same way North America was, with the Siberian coast facing an enclosed tropical sea. The Indian subcontinent and north
(formerly southeast) Asia form the new Siberia. The Gobi Desert is no longer in the rain shadow of the Himalayas, but doesn't exactly become
Europe resembles the old southeast Asia. Great Britain and Ireland look like the Indonesian islands of Sumatra and Borneo. Iceland resembles our
Philippines. Central Europe is the new New Guinea, wi