Some months ago, I created a series of maps and diagrams for @iguanodont‘s Birdbug worldbuilding project, representing the planet inhabited by their original species and its planetological data. This isn’t the first time I mapped out this planet, as I was also commissioned by Ripley back in 2020 back when I didn’t have nearly as much experience and knowledge as I do now. Two years later, I’ve been commissioned once again to revisit this world and its peculiarities.
This first map (in Equirectangular projection and poles-centered perspective) depicts the elevation for this planet, with a color gradient applied to the data.
Here is the same elevation data, presented without the color gradient.
This time, the elevation is presented with bodies of liquid water included, such as rivers, oceans, and lakes.
and in this one, the water is isolated from the other data, against a white background
Next, there are the surface temperatures that occur on this planet, the key to which is shown above. The four maps below show the seasonal temperatures for land and sea, in order of Northern Spring Equinox, Northern Summer Solstice, Northern Autumn Equinox, and Northern Winter Solstice.
Correlating closely to the above data is the snow and ice cover, which is fairly extensive on this planet owing to its high obliquity and distance from its star. Land ice only occurs where the snow falls and is compacted year-round, but snow and sea ice can be much more seasonal.
Seasonal precipitation levels were another important phase of this project, and the below diagram shows those levels for a given latitude (y-axis) on a given date (x-axis), with a key attached.
My reference for creating the above graphic is the figure below, which comes from a 2019 paper by A.H. Lobo and S. Bordoni titled “Atmospheric Dynamics of High Obliquity Planets”, and shows Earth’s precipitation levels compared to those of a planet with an 85° obliquity.
The following maps can now be better understood in light of these diagrams and keys.
-Northern Summer Solstice
-Northern Winter Solstice
I was also tasked with mapping out the extent and density of this planet’s vegetation (or at least its alien equivalent), and from this you can see how wildly it varies by season, with very few year-round holdings. Precipitation is a major factor in where it is possible for plants to flourish, but snow cover and the extreme temperature swings limit it too. Near either pole, for example, within the space of a year temperatures soar far above Earth’s upper limits and also plummet below freezing; if either extreme were to be the annual norm for a region, some plants might adapt to those conditions, but because of the wild fluctuation any adaptations to one extreme would leave plants especially vulnerable to the other. These regions, then, remain barren regardless of rainfall or brief windows of mild temperatures, while areas with less wide temperature ranges allow for at least brief periods of flourishing.
Determining the surface temperatures for this planet required a lot of background work. The first piece of the puzzle for this was knowing the number of daily hours of sunlight for a given latitude and date, which is exemplified first in this diagram for Earth:
and then for the Birdbug planet, below. Since this planet rotates on an axis of 60 degrees, there are many more latitudes within range of either pole that experience periods of sunlight and darkness lasting longer than a day. The higher the latitude, the longer this period lasts, with the poles themselves experiencing either condition for half a year at a time.
Another important factor is the height to which the sun is seen to rise (more scientifically, the angle at which the sun’s light hits parts of the planet’s surface), seen here first for Earth and then for the Birdbug planet. In these diagrams, white represents the sun reaching the zenith of the sky (meeting the surface at a 90° angle), and black represents the sun failing to appear above the horizon (meeting at an angle of 0° or below), while shades of green and purple stand in for angles between those extremes. For Earth and the Birdbug planet alike, the sun reaches the zenith within the bounds of either planet’s Tropic circles of latitude, and fails to rise at all only within the Polar circles of latitude; the difference in obliquity means that the Birdbug planet’s key circles of latitude are flipped compared to Earth’s.
The duration of sunlight and the angle at which that sunlight is reaches the planet’s surface determine a planet’s Insolation, that is, the amount of solar energy it receives. The first image below is a preexisting diagram of Earth’s Insolation, where it is measured in watts per square meter. The next two images are my own attempts at replicating this data for Earth, and then for the Birdbug planet.
As seen in the diagrams above, Insolation on the Birdbug planet differs from Earth not only in its latitudinal distribution, but also in its sheer intensity at the higher latitudes. Compared to Earth there are twice as many latitudes for which the sun is shining longer than one rotational period, and many of those latitudes see the sun shine at a direct or nearly direct angle, whereas the Polar circles of latitude on Earth see the sun shine much more obliquely.
Below, we can see the data that all the above figures were instrumental in finding: that is, surface temperatures. The first image is a preexisting figure that measures Earth’s mean surface temperatures by date and latitude, and below that is my attempt at replicating the data by my own process.
This is done not by just copying the seasonal Insolation data, but by also factoring in the yearly average for each latitude.
Above, we see the temperatures of the land by date and latitude, and below, we see the temperatures at the surface of the sea, which lag behind the land temperatures and remain comparatively mild.
Lastly, here’s an image I created to combine the snow and ice cover as well as the vegetation extent and density, as of the Northern Spring Equinox. This, along with the elevation map also seen here, is what I uploaded to maptoglobe.com in order to produce the screenshot at the top of this post.
These maps and figures (except for the preexisting ones) were all created in Photopea. Higher resolution versions of many of these images can be seen in my dedicated Reddit posts, linked below:
reddit post one, reddit post two
