By Michael Peter Galvin, Environmental Engineer. 14 JULY 2017

The term ‘Radiative Forcing’ that was first defined in IPCC reports is non measurable as it changes with altitude (temperature), due to moist adiabatic lapse rate the latent heat absorbed rises to a cooler upper atmosphere and latent heat is released on precipitation that cools and cleans the atmosphere and surfaces again. Dry cloudless deserts with little greenhouse effect are hotter than humid, cloudy places that which precipitate more often. There is more incoming solar radiation heating surfaces in the desert and high pressure system warm fronts adiabatically heating the air. In humid conditions however, increased cloud cover and precipitation is associated with low pressure systems that lowers air temperatures. Cloud cover and precipitation have negative forcing.

The hydrological cycle below shows how the incoming solar radiation heats surfaces creating evaporation and humidity that becomes cloud cover and latent heat is released on precipitation.

With reference to the Atmospheric Transmission Chart below, H20 has the highest Specific Heat Capacity and absorbs most of the UP-GOING 15–30% IR THERMAL RADIATION. Humidity just makes it feel hotter delaying the escape of latent heat however the cooler atmosphere does no work on the warmer surfaces and no change in internal energy of warmer surfaces by the cooler atmosphere. As you can see due to Specific Heat Capacities, CO2 and CH4 absorb less heat than H20 and are also in parts per million ie. 0.04% of air and parts per billion i.e.. 0.0002% of air respectively.

The NASA Earth Energy Budget Flowchart below confers with the Atmospheric Transmission Chart. The surfaces are heated in the first instant by DOWN COMING SOLAR RADIATION that heats the air near the surfaces and adiabatically heating the air further to create high pressure system warm fronts raising air temperatures. In fact cloud cover in this estimate reflects 20% of the incoming solar energy that which would be more as cloud cover increases and surface cooling when precipitation occurs. There is no apparent ‘forcing’ by the greenhouse gases on the surfaces in the flowchart below.

Due to Specific Heat Capacities between ocean and air, warm water creates warm wind high pressure systems that raises global air temperature and similarly cool water creates low pressure systems and cold fronts that lowers global air temperature. The incoming solar radiation heats surfaces in the first instant. There is also atmospheric adiabatic heating from the rise and expansion of heated air near surfaces and from Foehn winds down hills.

The reason i suspect GHG’s are a net thermal sink is by comparing air temperatures in a dry cloudless desert along the Equatorial where the sun is most direct and intense to air temperatures in a Tropical rainforest or rice farming agricultural land along the Equatorial where most ‘greenhouse effect’ exists and the GHG’s and cloud cover definitely keep it from getting too hot in the day and too cold at night, precipitation then cools and cleans the air and surfaces. In Cambodia for example the driest time of the year between Jun-Aug is the hottest and the cloud cover still builds up every day blocking the solar radiation heating surfaces and precipitates every several days cooling the surfaces again. Compare this to a dry cloudless desert region such as Death Valley that is in a rain shadow, the incoming solar radiation heating surfaces and heat island effects heating air near surfaces plus adiabatic heating high pressure systems makes air temperatures hotter in the desert than if there were cloud cover. Foehn winds downhill and convection superheat the air in the desert valley as it has steep hillsides either side.

In conclusion, deserts are hotter due to lack of greenhouse gases and cloud cover helping regulate temperatures than it is where it is humid, cloudy and precipitates more. High pressure systems are generally associated with dry weather and clear skies whereas low pressure systems are associated with cloud cover and precipitation. The ‘greenhouse effect’ is an important part of a healthy biosphere, water vapour and CO2 is plant food and the CH4 is an indication of biological degradation and drawing up of worms that which improves the soils. The greenhouse gases are just thermo regulators that mimic temperatures and help prevent it getting too hot in the day and too cold at night.