In Part 1 I discussed many instances where the Earth’s climate responded quickly to changes that happen on a regular basis. Events like seasons and volcanic eruptions all can cause the climate to respond very quickly to these events. Despite this there is a persistent belief amongst warmists that there is much more warming that is going to happen as a result of the CO2 emissions that have already happened. This would indicate that the climate responds slowly to changes.
This is where the idea of thermal inertia enters into the picture. The usage of thermal inertia in the terms of climate change is a very unusual usage of the scientific term. In normal usage it only applies when the steady state equations won’t apply because of the delay in the heat transfer into an object. In climate they have used it to say that the entire depths of the oceans will warm as a result of CO2 levels. They have created a delay so even if there isn’t warming, they can say that warming is taking place, but it is happening deep in the oceans and that is why it isn’t seen. This allows them to say that the warming will keep going for 100 or even 1,000 years even if CO2 is stopped now.
The name thermal inertia also implies that once CO2 is stopped, warming will continue. This is comparable to saying that once a pot starts warming up on a stove, it will keep warming up, even if it is removed from the stove. The basis for this is that CO2 will act like a stove for the entire future until thousands of years from now the global CO2 levels are reduced. Until then, the theory claims that CO2 will be a stove that will always be warming the Earth up. The idea of thermal inertia allows CO2 to be compared to a stove that is always on with the only temperature control being the concentration of CO2 in the atmosphere.
Thermal inertia got an early start in the story of global warming. That is because for a long period of time after CO2 concentrations started to rise, the temperatures did not. This was a real problem for warmists back in the 1970′s and 1980′s. They were predicting warming, but they were not seeing it. So they had to create a theory that proved warming was taking place even if they could not see it. Starting in 1958 there was reliable monthly CO2 data. Here is that data plotted against the global temperature anomaly for the period from 1958-1996.
In this manner the lag is justified because it would take time for the entire oceans to warm up. So instead of causing warming that can be observed by people the warming is taking place deep in the oceans where no one can see it happening, but we are assured that it is happening. This is where the idea of a time lag entered into the debate. It is not an idea that gets lots of attention, especially after the 1998 El Nino gave the warmists such a media boost, but it does show up when the idea needs to be presented that warming will keep happening for a long time (they even show the Earth sitting on a burner).
This warming of the oceans is blamed for the accelerating rise of the sea levels. The argument goes that as water warms up it expands and because the oceans are warming up they are expanding. Of course I have shown extensively that the rise in the ocean levels are decelerating and large drops in the oceans could be happening soon and in fact are already happening.
There are some really major problems with the idea of thermal inertia being applied to the oceans. The first is that all other atmospheric or solar events warm the atmosphere first before they affect the oceans. So the idea that CO2 will cause un-ending warming in the oceans before the effects are felt in the atmosphere is counter to all other responses of the atmosphere. When a volcano causes the Earth to cool, it cools the atmosphere immediately. It does not delay 40 years before the effect shows up in the atmosphere because it was cooling the oceans for that period of time. There is essentially no atmospheric delay for atmospheric effects.
The reason why is energy. As I stated in part 1, it takes ~3600 times more energy to warm the same volume of water as it does air. The ocean currents transfer more energy around the Earth than the atmosphere does. The oceans are in effect the energy storage unit for the Earth. When the atmosphere cools, the oceans release heat to the atmosphere. When it warms, the oceans take energy from the atmosphere. When Mount Pinatubo erupted, the atmosphere cooled, but in response to the thermal change the oceans transferred heat to the atmosphere. That is why the atmosphere recovered it’s temperature so quickly in the tropics. There is lots of warm ocean to transfer heat to the atmosphere. In the Northern Hemisphere were there is less ocean the cooling was more prolonged and took longer to recover.
As if that isn’t enough of a problem for thermal inertia, the other one is even bigger. Anyone who has gone swimming in a mountain lake will understand this clearly. The water on the top of the lake can be nice and warm, but swim down a few feet and the water can be very cold. That is because warm water is less dense and rises to the top of the water. In the oceans this effect is complicated by the salt, but warmer less salty water rises to the top. That warm water does not mix downward very well. If CO2 was primarily warming the oceans, then it would be seen primarily at the ocean surface. Once the water warms up, only something that disturbs the water can cause mixing.
Thermal inertia is self-defeating when it comes to the oceans. Since the behavior of the water changes with temperature, it limits the depth that the warming can reach. The more the surface of the ocean warms, the less mixing there will be at the ocean depths. The oceans in effect insulate themselves from additional warming. The oceans also do the same thing with cooling. By forming an insulating layer of ice that is less dense (floats, much like warm water), it slows the rate of cooling into the ocean depths. Water is a superb tool for regulating the Earth’s temperature. Since the warmest water will always be the top layer, the effects should be seen in the ocean temperatures. Of all the places on Earth, that is the one place that has seen the least warming.
The oceans are simply not showing the evidence of global warming. Since the theory of thermal inertia REQUIRES that the oceans warm up and the oceans are not showing it, then there must be a problem with that theory.
Without thermal inertia to allow for long delay times for warming to happen and all other evidence points to quick response in the Earth’s climate. The only thing that remains is the idea that we are currently facing the FULL effects of the worlds CO2 concentration of 390 ppm. Of course that full effect is an almost statistically meaningless variation in the average temperature that may or may not have been caused by the change in CO2 concentration. The likely truth is that there has been some trace warming as a result of CO2 levels, but the magnitude of the impact is small enough that it cannot be distinguished from the noise.
The key aspect of this is that there is no future warming to worry about from CO2 levels. There is only what has happened now. For the past 5 years the evidence of warming has reversed. The rise in the oceans appears to be ending while CO2 levels continues to rise. If the ENSO is removed there is almost no trend in the ocean temperatures. Understanding the time response of the Earth’s climate makes it clear that there is little reason to be concerned with the CO2 levels in the atmosphere. The effects are here and they are rather unimpressive.