The astronomical Milankovitch cycles are otherwise known as precession. They are named after Serbian geophysicist and astronomer Milutin Milanković. Milanković mathematically theorized that variations in eccentricity, axial tilt, and precession of the Earth’s orbit determined climatic patterns on Earth through orbital forcing.  (Orbital forcing is the effect on climate of slow changes in the tilt of the Earth’s axis and shape of the orbit. These orbital changes change the total amount of sunlight reaching the Earth by up to 25% at mid-latitudes. )
The Earth’s axis completes one full cycle of precession approximately every 26,000 years. At the same time the elliptical orbit rotates more slowly. The combined effect of the two precessions leads to a 21,000-year period between the astronomical seasons and the orbit. 
Bicentennial quasi-periodic Total Solar Irradiance (TSI) variations define a corresponding cyclic mechanism of climatic changes from global warmings to Little Ice Ages. TSI variations are the fundamental cause of climate variations. Other factors involved are changes in the Earth’s orbit, inclination of the Earth’s axis, and the astronomical Milankovitch cycles. 
The term albedo (Latin for white) is commonly used to apply to the overall average reflection coefficient of an object. A distinction is made between “bond albedo” and “geometric albedo”. The bond albedo is the total radiation reflected from an object compared to the total incident radiation from the Sun. For example, the planets are viewed by reflected sunlight and their brightness depends upon the amount of light received from the sun and their albedo. 
There is an “energy budget” which is determined by the average annual difference between solar radiation energy coming into our atmosphere and the reflected solar radiation and longwave radiation energy outgoing into space. The “Albedo of the Earth” plays a role in whatever the “energy budget” averages out to be.  This narrows down to the “bond albedo”, the total radiation reflected from an object compared to the total incident radiation from the Sun. 
The debit and credit parts of the “energy budget” are always in an unbalanced state: that is the basic state of the climatic system, i.e. surpluses and deficits. If the Total Solar Irradiance (TSI) increases, the “enthalpy” – a defined thermodynamic potential, consisting of the internal energy of the system plus the product of pressure and volume of the system – becomes positive; if the TSI decreases, the “enthalpy” becomes negative. 
The “bond albedo”, the total radiation reflected from an object compared to the total incident radiation from the Sun, increases during a deep cooling and decreases during a warming, that is to say, more of the Total Solar Irradiance (TSI) is reflected from the Earth during a deep cooling phase. An upcoming “Grand Minimum” of the TSI leads to a deficit in the “energy budget” of Earth and consequently a Little Ice Age. 
Ever since the early 1990s, there has been a decrease in the TSI and thus a decrease in solar energy absorbed by the Earth. From this, Habibullo Abdussamatov goes on to suggest “that this decline as a whole will correspond to the analogous TSI decline in the period of
Maunder minimum…” (The Maunder Minimum is the name used for the period starting in about 1645 and continuing to about 1715 when sunspots became exceedingly rare. The Maunder Minimum coincided with a period of lower-than-average European temperatures. Background: Canopy Of Cold Descends, Ersjdamoo’s Blog, November 20, 2014.)
This all means that the Earth will have a “negative balance” in the “energy budget” in the future “because the Sun has entered the decline phase of the quasibicentennial cycle of the TSI variations. This will lead to a drop in the temperature and to the beginning of the epoch of the Little Ice Age approximately after the maximum of solar cycle 24 since the year 2014.” 
(Solar Cycle 24 is the 24th solar cycle since 1755, when extensive recording of solar sunspot activity began. Solar Cycle 24 is the current solar cycle, and began on January 4, 2008. It is on track to be the Solar Cycle with the lowest recorded sunspot activity since accurate records began in 1750. )
“Now we witness the transitional period from warming to deep cooling characterized by unstable climate changes when the global temperature will oscillate (approximately until 2014)…” After 2014, apparently, the minimum of the Total Solar Irradiance (TSI) of the quasibicentennial cycle occurs in Solar Cycle 27+1, around 2043, and the beginning of the “deep cooling” phase arrives around 2060. 
Habibullo Abdussamatov believes that the “anthropogenic discharges” of carbon dioxide and such is negligible compared with the amounts of natural flows (carbon dioxide, water vapor, and dust) from the ocean and land to the atmosphere via such things as volcanoes and the sea. Even a “weak breath” of the ocean “can change dramatically the carbon dioxide level in the atmosphere. Natural causes play the most important role in climate variations rather than human activity since natural factors are substantially more powerful.” It is the Sun, according to Abdussamatov, which is the main factor controlling the climatic system, and even relatively minor long-term TSI variations can have serious consequences for the climate of Earth and other planets.
The Earth’s climate will change every 200 or so years (plus/minus 70 years), caused by bicentennial cyclic Total Solar Irradiance (TSI) variation. The forthcoming period of deep cooling will last approximately until the beginning of the next century, predicts Abdussamatov. Especially affected will be those populations situated far from the equator.
——- Sources ——-
 “Milankovitch cycles”, Wikipedia, November 21, 2014.
 “Orbital forcing”, Wikipedia, November 21, 2014.
 “Grand Minimum Of The Total Solar Irradiance Leads To The Little Ice Age”, by Habibullo Abdussamatov. November 25, 2013. http://scienceandpublicpolicy.org/images/stories/papers/originals/grand_minimum.pdf
 “Albedo of the Earth”, http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/albedo.html
 “Solar cycle 24”, Wikipedia, November 21, 2014.