It depends on where on Earth you may be. If you are one mile beneath the surface of the Atlantic Ocean, for example, you'll find different pressure than at one mile below the summit of Mount Everest. If the questioner is asking about air pressure, assuming their is a place which is at such an altitude, then I imagine the answer is somewhere already available within Google's vast pages (avoiding Wikipedia of course which claims certain schools to be Schools of Witchcraft and Wizardry for months on end before someone adjusts and amends the comments!) and I can only gather from my infrequent forays into that particular site that the rest is similar and subjective rather than informative or accurate or in any small way factually correct to any degree.
Below sea level atmospheric pressure increases with depth. Air pressure at sea level is about 14.7 psia. Air pressure below sea level would be slightly higher.
Assuming you are talking about air pressure, atmospheric pressure is created by the weight of the air resting against the earth. the higher up you go, the less air stacked on top of itself, and the pressure is less, until there is no more air at all (space). The pressure of air at sea level is relatively the same around the world because of all the water flows to the same level. this obviously changes with storms and hurricanes - as those move some of the air out of the way. So if you were to go below sea level, there would be more air on top of you, and the pressure would be higher. In death valley (well below sea level) the atmospheric pressure is much higher than at sea level. To answer the question, No, pressure is not negative below sea level. It is greater than at sea level.
At a depth of 3,000 meters below water level, the pressure can be calculated using the formula: pressure = depth × density of water × gravitational acceleration. The average density of seawater is about 1,025 kg/m³, and gravitational acceleration is approximately 9.81 m/s². Thus, the pressure at this depth is roughly 30,000 kPa, or about 300 times atmospheric pressure (1 atm being approximately 101.3 kPa).
The standard fuel pressure for a 1998 Chevy 3500 with a 454 engine is 50 PSI. If fuel pressure drops much below this level, the fuel injectors will not work properly.
Diving 30m below sea level increases the pressure on our bodies due to water above compressing our lungs and tissues more. In contrast, at a building 30m above sea level, the pressure is decreasing compared to sea level, but the effects on the body are negligible in most cases. The change in pressure underwater can lead to issues like decompression sickness if not managed properly.
death valley 282 feet below sea level
The pressure under 1 mile of the Earth's crust is approximately 2,300 pounds per square inch (psi). This pressure increases with depth due to the weight of the overlying rock and material.
Colorado is the major U.S. state with the highest average elevation, with much of the state being over a mile above sea level.
I know that the dead sea is below sea level
You would need to check the PSI level. This will determine how much refrigerant you have in your system. You can get a Pressure chart on the link below. It will tell you what the PSI should be at the Current Ambient temp.
Sub energy pretty much explains itself: It is below energy level
The pressure 1 mile under the Atlantic Ocean is approximately 2,300 pounds per square inch (psi). This pressure increases as you descend further into the ocean due to the weight of the water above.