What are the results of latitudinal radiation imbalance?
The result of this imbalance is an accumulation of excess energy in the Earth system over time. The size of the imbalance, or equivalently, the rate of energy accumulation in the Earth system, is the most fundamental metric determining the rate of climate change.
How does net radiation vary with latitude?
Averaged over the year, the net radiation at the top of the atmosphere is downward at low latitudes and upward at high latitudes. These local imbalances reflect the differing meridional profiles of insolation (incoming solar radiation) and outgoing terrestrial radiation pictured in Figure 7.
What causes the energy imbalance along the latitude?
The differences in reflectivness (albedo) and solar illumination at different latitudes lead to net heating imbalances throughout the Earth system.
What is the net radiation balance?
Earth’s net radiation, sometimes called net flux, is the balance between incoming and outgoing energy at the top of the atmosphere. It is the total energy that is available to influence the climate.
What happens when net radiation is negative?
We know that the earth will cool down as long as net radiation is negative. Each hour where an energy deficit is observed will result in further cooling. Therefore, the coolest temperatures are not observed at the time of maximum hourly energy deficit, but at the time of maximum cumulative energy deficit.
What is net longwave radiation?
Introduction. Surface net long-wave radiation (L n ) represents the difference between the upward long-wave radiation emitted from the surface and the downward long-wave radiation from the atmosphere. It is the quantity of heat loss from the ground surface through L n exchange (Zhou et al. 1990).
How does net radiation differ at the equator compared to the poles?
The pattern of net radiation is more symmetrical: negative (green) at the poles, balanced (yellow) at the mid-latitudes, and positive (red) at the equator.
Why does surplus energy need to be transferred between low and high latitudes?
Energy is transferred from lower latitude energy surplus areas to higher latitude energy deficit areas by atmospheric circulation. If there was no atmospheric circulation, lower latitudes would get hotter and hotter and higher latitudes colder and colder.
Between what latitudes is the net energy gain from solar radiation?
Net radiation is zero when the incoming and outgoing components are in perfect balance, which does not occur too often. Between 40˚ N and 40˚ S, the Earth possesses a net gain of energy. Poleward of 40˚ N and 40˚ S, there is a net loss of radiation.
Why is net radiation negative?
Net radiation is negative at each pole because the amount of energy those areas absorbed from incoming sunlight was less than the amount they reflected and/or radiated as heat.
How does the atmosphere affect the net radiation budget?
GREENHOUSE EFFECT Increasing concentrations of greenhouse gases such as carbon dioxide and methane increase the temperature of the lower atmosphere by restricting the outward passage of emitted radiation, resulting in “global warming,” or, more broadly, global climate change.
How is net radiation determined?
Net radiation is the sum of short-wave radiation and long-wave radiation. It can be determined either by direct measurement or by calculation. For the direct measurement, net radiometer is usually used after calibration. The calibration allows the definition of a parameter termed as “net radiometer sensitivity”.
Why does energy flow from low latitudes to high latitudes?
Because there is an energy surplus at low latitudes and an energy deficit at high latitudes, energy will flow from low latitudes to high. This energy is transferred poleward as latent and sensible heat —warm ocean water and warm, moist air move poleward, while cooler water and cooler, drier air move toward the Equator.
What are the implications of radiation balance?
Implications. The radiation balance changes throughout the day and year owing to incoming solar radiation, which has the largest effect on the radiation balance, followed in importance by the cloud cover. The next major factor is the slope of the surface, which affects the amount of solar radiation absorbed.
What is the net radiation from the earth’s surface?
So the net radiation for the Earth’s surface as a whole is zero, as expected, with global incoming shortwave radiation exactly balancing global outgoing longwave radiation. Because there is an energy surplus at low latitudes and an energy deficit at high latitudes, energy will flow from low latitudes to high.
What are the factors that affect net radiation?
In general, net radiation is dependent on the latitude (solar radiation), the surface properties (reflectivity or albedo and emissivity), the atmospheric conditions (clouds) as well as the topography and surface cover of the surroundings (shading effects, longwave emission). Figure 3.