From a physics standpoint, the distance you can jump should be related to the square of how fast you can move, plus the length of your stride. In game terms, a roughly human sized and shaped character can jump:
Creatures in the water don't jump, they breach. The only important measure here is the creature's current speed - if going fast, you can leap farther or higher out of the water.
When figuring the character's current speed, assume he can be moving at any speed he could have accelerated or decelerated to during that turn even if he jumps before he would have moved this distance on a tactical map, if he can get at least two meters of a running start. For example, a character with a running move of 7 and a Basic Move of 7 can jump any distance up to 6×(7×7/100)+2 = 4.9 meters even if he can only run two meters from a standstill before reaching the point from which he can jump. If he spent the previous turn running, he can use his sprint bonus to leap up to 6×(7×8/100)+2 = = 5.4 meters.
Regardless of how far you jump, you still only move at your current speed or Basic Move (whichever is more) as you fly through the air. While in the air, you can neither change direction nor halt your flight.
A character jumping from a moving vehicle or platform can use the vehicle's or platform's current speed to leap as if making a running long jump, even if not running while on the vehicle or platform. If you are moving faster than your running move, you will fall down when you hit the ground.
If you have the Leaper advantage, add this to your basic speed but not to your current speed when calculating how far and how fast you can jump. Your average speed when making a series of jumps cannot exceed your Ground Move (or other environmental move for different terrains, such as Climb Move for tree-dwelling critters, but including the Sprint bonus or Enhanced Move is applicable and you have had enough time to accelerate to that speed). If this is the case, you must pause to prepare before each jump for long enough that your average speed is no move than your Move. Treat this pause as a ready maneuver.
If you make a jumping or acrobatics roll, you can add another 0.5 meters to the distance you clear in a high jump ((linear dimension)/4 for SM different from 0). A jumping roll at -3 lets you add 1 meter to the distance you clear with a high jump ((linear dimension)/2 for SM different from 0). You will need to succeed another acrobatics roll to land on your feet after the jump.