this is called the jet stream
The Alps mountain range forms a natural boundary between France and Italy.
Lake Victoria acts as a boundary between Tanzania, Uganda, and Kenya. Another natural boundary between these countries is the Kagera River.
The Himalayan Mountains is the natural boundary between China and India. China and India have fought battles over disputed parts of this boundary.
The Oregon Treaty set the boundary at the 49th Parallel.
which waterways make up almost half the boundary between the united states and Canada
No
Such a boundary is called a front.
As long as the body and the surrounding atmosphere are at different temperatures, there will be heat transfer between the two.
There is no definite boundary between the atmosphere and outer space. It slowly becomes thinner and fades into space. An altitude of 120km (75mi) marks the boundary where atmospheric effects become noticeable during reentry. The Kármán line, at 100km (62mi), is also frequently regarded as the boundary between atmosphere and outer space. Three quarters of the atmosphere's mass is within 11km (6.8mi; 36,000ft) of the surface.
the atmosphere
A boundary between two air masses of different temperatures and humidity is called a front. If a cold front meets a warm front head on, there is a possibility for a violent storm.
A "front" is the interface between two air masses of different temperature.
In the mantle, temperatures range between 500 to 900 °C (932 to 1,652 °F) at the upper boundary with the crust; to over 4,000 °C (7,230 °F) near the boundary with the core.
Magnetosphere.
Contrasting in visual arts means the difference between light and dark, and all of the grey areas in between. It could also mean contrasting ideas in a single piece of art.
The Moon's gravity causes the lack of atmosphere (any possible atmosphere evaporates out into space in a fairly short time); and the lack of atmosphere causes the extreme temperatures.
The Moon's gravity causes the lack of atmosphere (any possible atmosphere evaporates out into space in a fairly short time); and the lack of atmosphere causes the extreme temperatures.