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The Global Context: Climate, Hydrology, and the Critical Zone - Basic Aspects of Global Climate

5 important questions on The Global Context: Climate, Hydrology, and the Critical Zone - Basic Aspects of Global Climate

Which relation does the Stefan-Boltzmann law give?

It gives the rate at which radiation energy is emitted, which depends on the absolute temperature of the surface, an universal constant (sigma) called the Stefan-Boltzmann constant and the dimensionless quantity emissivity (epsilon).

What does Wien's displacement law relate?

It relates the Maximum radiant energy flux (labda max) with the absolute temperature (inverse relation). Higher T -> lower labda

What is the lapse rate and inversion?

The vertical gradiënt in the troposphere which is on average 6.5 C/km. This gradiënt can be highly variable and even be temporarily reversed which is called inversion leading to a significant change in the buoyancy of vertical moving parcels of air and therefore of water vapor and heat transport.

What is the El Nino-Southern Oscillation in general?

It's a quasi-cyclic, wave-like phenomenon with a period of 3 to 7 years. It consists of an oscillation between a warm phase (El Nino), which is characterized by abnormally high sea-surface temperatures (SSTs) occurring along the coast of Peru accompanied by low atmospheric pressure over the eastern Pacific, and a cold phase (La Nina) with low SST in the easter Pacific and the opposite pressure anomalies.

According to considerable evidence, this oscillatory phenomenon doesn't require outside forcing.

How is the magnitude of the NAO presented?

The strength of the NAO is given by the NAO index, defining the normalized monthly difference between the sea-level-pressure anomalies at weather stations in the Azores and Iceland. A positive mode leads to stream and weather systems moving eastwards across North America and the North Atlantic parallel to the latitude lines (zonal flow). The negative phase characterizes a weaker North-South pressure gradient blocking the jet stream and weather systems inducing a meandering path with a longitudinal component (meridional flow).

The question on the page originate from the summary of the following study material:

Physical Hydrology Third Edition | 9781478628071 | S Lawrence Dingman

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