1. Introduction
So far, the predictions of climate changes are based on hypotheses and
calculations of evolutions for the distant future as reported in
successive
Intergovernmental
Panel on Climate Change (IPCC) reports (IPCC, 2014; IPCC, 2019). These
reports result from an international consensus predicting evolutions in
distant future, trends being still small but nevertheless detectable
today. The consensus is adopted almost universally although
controversies exist, the dispatching of which is limited to articles in
open access archives and magazine outlets [Dunlap & Jacques, 2013].
Until recently, global climate changes were assigned to imbalanced
inputs and outputs of electromagnetic infrared radiations and to
anthropogenic greenhouse gas, especially CO2, considered
as sources of radiative anthropogenic heat release (rAHR) (IPCC, 2014;
NASA, 2009; Mackenzie & Lerman, 2006) without consideration to any
other sources of internal heat considered as negligible, notably
anthropogenic heat release (eAHR) generated by the sources of energy
produced and exploited by humanity. In the past, only rAHR related to
greenhouse gas was taken into account and considered as absorbed
predominantly by oceans (Hansen, et all, 2011; Trenberth et
al., 2014; IPCC, 2019) except by a minority of climate-skeptic people.
rAHR is said resulting from electromagnetic radiative flux that amounted
annually from 0.5 to 1W/m2 in the early 2000s
(Trenberth et al., 2014; IPCC, 2019), i.e. between 8.5 and 17 x
1021 Joules (8.5 and 17 ZettaJoules (ZJ)), the mean
value being c.a. 0.79 W/m2. Regardless of their
origin, the heat energy that warms Earth has to be balanced by
compensation or evacuated to space otherwise the Earth would grow warmer
and warmer over the years. Water cycle has been recognized for years as
an important factor in climate control through evaporation-condensation
phenomena despite limitations due to uncertainties on available global
data (Allan & Liepert; 2010). In general, global ice was considered
negligible heat absorber relative to oceans (Hansen et al., 2011). Based
on outstanding facilities including satellites, NASA is the reference
body to quantify ice imbalance and its role on the polar environment
(Scott & Hansen, 2016). The occurrence of dramatic global ice loss is
now certain, especially over the recent years, and concerns different
ices, namely ice caps, sea ice, glaciers and permafrost (Rignot et all,
2019; Slater et all, 2021). Ices melting is generally considered as a
source of ocean rise (Allan & Liepert; 2010) in addition to
temperature-dependent dilatation. The contribution of eAHR to global
warming neglected in the past is more and more regarded as an actor. The
context and the history were well introduced in a recent publication
(Yang et al, 2017) in which the authors proposed an algorithm to
evaluate global eAHR. This approach consisted in calculations based on
heat energy estimates derived from urban zones. Although there were
limitations, the algorithm provided multi-scale anthropogenic heat
information said reliable and useable for further research on regional
or global climate changes and on urban ecosystems despite difficulties to
establish ratios for converting energy consumption to anthropogenic
heat.
We recently proposed a different approach (Vert, 2021) based on ice
loss, fundamentals of chemistry and physics and annual global energy
consumptions derived from various sources (fossil ones, biomass, nuclear
electricity, etc.) found converted in oil-equivalents (Martin-Amouroux,
2015; BP, 2019). According to (Manowska, & Nowrot (2019), eAHR
corresponds to c.a. 60 % of the global energy consumption, the rest
being consumed to generate work. Accordingly, it was shown that
anthropogenic heat released from all the energy sources in the low
atmosphere between 1994 and 2017 provided enough thermal energy (7.2 ZJ)
to melt 77% of the 28 trillion tonnes of disappeared ice reported
recently for the same long period (Slater et all, 2021). Therefore, eAHR
estimated over 23 years was effectively negligible when compared with
the 8.5 to 17 ZJ estimates of annual rAHR. As ices imbalance reflects a
thermal energy supply regardless of its origin, why rAHR increases
assigned to CO2 greenhouse gas do not cause much greater ices imbalance
than presently observed?
In attempt to bring in an answer to this question, let us consider that
solar radiations have been heating the global environment over billions
of years without dramatic heat accumulation despite occurrence of short
and long and more or less important local ups (high temperature) and
downs (glaciation) periods. The relative stability included natural
greenhouse effect assumed at the origin of a 33°C excess of average
Earth temperature. Nowadays, eAHR, rAHR and any other sources of heat on
Earth have to be managed similarly and simultaneously to solar heat to
keep Earth’s environment and climate under relative control and
compatible with Life. Indeed, the Earth can be schematically considered
as a huge globe with land, solid matters, surface water and atmosphere
heated internally since no matter or molecule can escape in
intersidereal space. Rejection of a large part of infrared
electromagnetic waves to space is the consensual mechanism largely
adopted in the world (IPCC, 2014 and 2019). However, if natural
greenhouse effects cause a 33 °C excess of temperature on Earth, the 2-4
°C rise expected from the sole doubling of anthropogenic
CO2 concentration in part per millions of atmosphere
seems logically disproportionate.
A few thousand years ago, humans began to use biomass as sources of heat
and light. eAHR remained very small compared with solar inputs until
about 150 years ago when humans began to exploit fossil sources and,
more recently, nuclear plants and renewable resources for the production
of electricity in order to satisfy work, heat and comfort needs. The
side effect was the appearance of eAHR in the low atmosphere in addition
to rAHR in the high troposphere (Yang et al.; 2017). Earth can be
compared to a mammalian body which has its metabolism generating heat in
a closed space, the body. This body which burns foods has to be cooled
down to keep its temperature constant. Based on this analogy, the
present article aims to compare Earth’s water with the refrigerant that
controls the temperature inside a refrigerator; a simpler case where
inner heat has to be eliminated. Results are discussed relative to
global warming and climate changes.