Climate Change, Baltic Herring And The Reformation?

Guest Opinion: Dr. Tim Ball –

Baltic Herring –

The Pope claims climate change is threatening the world and urges action to stop global warming. Many debate his motive, because the major objective of his new partners is reduced population through abortions and birth control, which contradict Catholic teaching. There is another possible motive, the impact of climate change on the church in history. The greatest challenge to the Catholic Church was the Protestant Reformation started in 1517 by Martin Luther and culminating in the 1648 Peace of Westphalia. Two basic situations trigger revolutions, failure of the food supply and leaders who refuse to answer to the people. Both triggered the Reformation revolution and resulted from climate change – global cooling.

A major, reliable, source of food is central to a strong economy. Surplus food creates surplus time and societies use that time to create economies. As Allan Savory noted,

“Without agriculture it is not possible to have a city, stock market, banks, university, church or army. Agriculture is the foundation of civilization and any stable economy.”

It is important to remember that an Agricultural Revolution preceded the Industrial Revolution.

Many civilizations are built on enhanced food supply and fishing. The Hanseatic League, (Figure 1) is a classic example.

“The Hanseatic League (also known as the Hansa) was an alliance of trading guilds that established and maintained a trade monopoly along the coast of Northern Europe, from the Baltic to the North Sea, during the Late Middle Ages and Early modern period (circa thirteenth–seventeenth centuries).”

Figure I

The region is a good agricultural region, but the herring fishery in the Baltic contributed greatly to the food supply and the economy. As one authority claimed,

“The Scandinavian herring fishery of medieval times may have been the most influential fishery in history.”

The expansion of the herring fisheries began during the Medieval Warm Period and quickly became economically and religiously important.

“In 1202 the Danes captured all the most important citizens of Lübeck and the cities fleet at Scania, while they attended the autumn trading at the Baltic herring fishery in the Sound. That the Danes were able to exploit the annual trade fairs to seize the entire merchant elite and the merchant fleet of Lübeck, attests to the importance of the herring trade in the Baltic and Europe in the medieval period.”

“As salted Scandinavian herring become recognized as a high quality product that was relatively cheap and easy to produce, the fishery literally exploded in the late 13^th century. With populations of herring so rich that some writers referred to them as being able to be “caught by the bare hands”, the fishery grew to more than 35,000 fishermen, and fed a good portion of Western Europe. The demand for herring was so high, that the customs registers of some towns, such as Lubeck, Germany where the herring fishery came to be based, indicated herring as the most important trade item in some years. As trade in herring increased, so did other commerce. Markets for herring soon expanded to include other goods and created trade ties between East and West.”

The economic development is understandable but what made the herring fisheries more influential than any other? The answer is a religion.

“Saltwater fish had long been part of the diet of the people living around the Baltic Sea as demonstrated by archaeological finds, and by the eighth and ninth centuries a large scale trade in herring had developed in the region. From the ninth century the steady advance of Christianity in Europe produced a new and increasing market as eating habits changed in accordance with the regulations for fasting that required the laity to abstain from meat for as many as 182 days in the year. Herring proved an ideal substitute. Gutting, removing the head, and preserving in salt could extend its shelf life for up to two years. It could be transported for long distances. And above all, it was cheap. The religious requirement for abstinence created a demand for fish that could not be met all year round by freshwater resources in inland Europe and ocean fish, and in particular herring, fulfilled this need in abundance.”

Historians provide reasons for the decline of the League, but generally overlook changes in nature, including climate. This is not surprising because they see humans as active agents in nature, not as passive recipients of natural changes. One reason for this is what they see as the dark shadow of climatic determinism, the paradoxical, anti-Darwinian view that nature does not control human behavior. Here is one set of human reasons.

“The individual cities which made up the League had also started to put self-interest before their common Hansa interests. Finally the political authority of the German princes had started to grow — and so to constrain the independence of action which the merchants and Hanseatic towns had enjoyed.”

Followed by another that at least makes oblique reference to fish stocks.

“Such actions led to the English, Flemings and Dutch developing the North Sea fisheries and their direct trade with Prussian cities more strenuously which, exacerbated by a fluctuation in herring stocks in the Sound, marked the beginning of a long period of decline for the Baltic fisheries as a trans-regional trade centre with the last Scania fairs being held in 1658.”

The change was more than “fluctuations”, it was a steady decline in the Baltic herring stock as conditions changed. Notice the dates on the map are 1267 – 1669 A.D, which covers the period of temperature decline from the Medieval Warm Period (MWP) to the nadir of the Little Ice Age (LIA). (Figure 2).

Figure 7c in the 1990 IPCC Report provides a reasonable approximation of temperature trends for the period of existence of the Hanseatic League.

Figure 2: Source: After 7c IPCC (1990)

H.H. Lamb explains the mechanisms and provides extensive examples of the changing global weather conditions from the MWP to the LIA (pages 440 to 473 in Volume 2, Climate, Present, Past and Future). It identifies the proxy evidence of declining temperatures, increasing precipitation and storminess, associated with a southward shift of the circumpolar vortex.

“The general turn towards colder climates from A.D. 1200-1400 onwards, accompanied by shifts of the zones of most cyclonic activity as the polar cap and the circumpolar vortex expanded, and which in the seventeenth century seems to have produced a world-wide cold stage.”

On pages 451-452 Lamb itemizes nine indicators of,

“The course of the climatic deterioration over five centuries from A.D.1200…”

Item 4 says,

“Increasing wetness of the ground and spread of lakes and marshes in many places in northern, western, and central Europe (and it is thought all over northern Russia and Siberia.)”

Item 7 records,

“In the records of harvest failures, rising prices of wheat and bread, famines, tithes and taxes remissions (sometimes with reasons given.”

All these changes impacted the Baltic Sea in significant ways. Even though connected to the North Sea it is essentially a landlocked body of water (Figure 3).

“The Baltic is a large semi-enclosed sea with positive freshwater balance and restricted water exchange both with the Kattegat and between the interior sub-basins.”

“The Baltic Sea is a unique sea area. Even though the Danish straits connect it to the Atlantic Ocean, its salinity is very low (only about one fifth of the salinity of the oceans).  The Baltic Sea is also shallow. Its average depth is about 54 metres,”

Figure 3

Temperature is a critical variable for fish. However, salinity is important for saltwater species like the Baltic herring.

“The annual mean salinity in three different depth intervals decreased with around l psu during the period 1977-1990. It is found that this was due to an increased freshwater supply. The increased freshwater supply also impeded the import of saltwater from the Kattegat, thereby decreasing the salinity in the deeper parts of the Baltic Sea. It is argued that the changed vertical distribution of salt within the Baltic Sea in the same period was partly due to increased vertical mixing.”

Similarly,

“At specific locations within the Baltic Sea, thermoclines and haloclines can create rapid spatial and temporal changes in temperature (T) and salinity (S) exceeding 10°C and 9 psu with seasonal ranges in temperature exceeding 20°C.”

Despite this, the herring evolved to the conditions.

“Due to its wide salinity tolerance range, Baltic herring is able to live and reproduce in almost every part of the Baltic Sea despite of the varying environment.”

However, as a result

“…the abundance and biomass of herring fluctuate from time to time even strongly.”

Ironically, in a study for global warming,

“Substantial ecological changes occurred in the 1970s in the Northern Baltic during a temporary period of low salinity (S). This period was preceded by an episodic increase in the rainfall over the Baltic Sea watershed area.”

“The results suggest a critical shift in the S range 5–7, which is a threshold for both freshwater and marine species distributions and diversity.”

It appears that by the 16^th-century conditions deteriorated as a combination of increased inflow, due to higher precipitation including snowfall and reduced evaporation that caused temperature and salinity levels to fall below even the herring’s tolerance. Harvest and fishing failures combined to create economic collapse, famine, population decline, and power struggles.

“At the start of the sixteenth century the League found itself in a weaker position than it had known for many years. The rising Swedish Empire had taken control of much of the Baltic…. The individual cities which made up the League had also started to put self-interest before their common Hansa interests. Finally the political authority of the German princes had started to grow — and so to constrain the independence of action which the merchants and Hanseatic towns had enjoyed.”

As these events unfolded, the Catholic Church increased the cost of Indulgences. Purchase an Indulgence for the remission of severe penances and you eased and accelerated the path to heaven. They were the Medieval equivalent of carbon credits, especially as they benefited the rich. They were Martin Luther’s first complaint.

Besides lack of food, the people could not obtain the fish essential to practice their faith, that is,

“the regulations for fasting that required the laity to abstain from meat for as many as 182 days in the year.”

Generally immune to these deprivations German Princes also did not care that most peasants could not afford indulgences. Although their political power increased the economic downturn impacted them, so the Princes apparently found indulgence costs becoming onerous. Luther nailed his Ninety-Five Theses to the church door in Wittenberg, a city located in the heart of the Hanseatic League.

It is possible the Princes allowed Luther’s revolution because of the economic conditions. Not only did the church demand more money for indulgences but also they spent it profligately. As Luther’s Thesis 86 notes,

“Why does the pope, whose wealth today is greater than the wealth of the richest Crassus, build the basilica of Saint Peter with the money of poor believers rather than with his own money?”

Pope Leo X responded to Luther with an Encyclical Exsurge Domine (Arise O Lord). Its final exhortation is remarkably similar to Pope Francis’ condemnation of climate skeptics.

“If, however, this Martin, his supporters, adherents and accomplices, much to our regret, should stubbornly not comply with the mentioned stipulations within the mentioned period, we shall, following the teaching of the holy Apostle Paul, who teaches us to avoid a heretic after having admonished him for a first and a second time, condemn this Martin, his supporters, adherents and accomplices as barren vines which are not in Christ, preaching an offensive doctrine contrary to the Christian faith and offend the divine majesty, to the damage and shame of the entire Christian Church, and diminish the keys of the Church as stubborn and public heretics.”

If Pope Francis knew climate history, he would pray for warming or at least a continuance of current conditions to continue as global cooling caused serious problems in the past.