THE GALICIAN CLIMATE ALONG THE HISTORY

(The text was prepared by Spanish participants of EFW 2007 from the Galicia Region, on the basis of the text of F.D.Fierros, professor in Santiago de Compostela University)

65 million years - tropical climate. Following the explanations given by the geographer Augusto Perez Alberti we can find signs of this fact in the deposits of lignite of As Pontes and Meirama.

Tertiary second half- wet climate.

Quaternary beginnings - dry climate.

120.000 years - like nowadays. The temperature was only a couple of degrees higher and so was the humidity.

80.000 years - unknown

50.000-11.000 years - colder climate/ higher humidity. Alpine landscapes. From this age the temperature increased between 1 and 3 degrees, the maximum accepted increasing. Francisco Diaz Fierros, professor of Pedalogy (study of the soils) in Santiago de Compostela University is one of the most important specialists in Paleoclimatology. He also says that the maximum rise in temperature in the northern hemisphere from the last glaciation is only half a degree; he also considers that bigger figures are excessive.

15.000 years. The temperature grows after a short cold period, called Dryas (2.000 years).

13.000 years. Climatic conditions were like nowadays. Diaz Fierros says that the climate that affected Galician people is postglacial.

6.000 years - optimum climate. Maximum expansion of the oak in Galicia. They would cover 60% of the territory, except the high areas or the wetlands. This was the primeval landscape of our history: Shall we be able to restore itto its original state?

Iron Age settlement (hill fort) V - VI BC. Period of cooling and rainfall that forced the Germanic people migration, on the contrary it seems that in the Roman Pax (peace) the climatic conditions were better. Higher temperatures meant an important moment in the agricultural expansion (only half a degree more in the annual average).

Archeological remains of the blast furnaces.

lst-2nd centuries - outstanding variation of the sea level. Anyway Diaz Fierros observes that the variations of the coastal line are not always motivated because of a climatic change. 1st - 2nd - 3th centuries (Roman peace and sun). Worsening of the climate at the end of this period, "but in Galicia, frequently we don't know for sure if this worsening is the consequence of the cold or of the rainfall", the professor signs. Erosion processes and pollen samples (from the peat bogs of the Xistral range) disclose an expansion of the forest and an abandonment of the agricultural zones, maybe caused by human actions, by the climate or by the higher forestry cultural level of the Germanic people that arrived at our country from the north of Europe. Anyway, the real fact is that the increase of the forest coincides with the Germanic settlement in Galicia.

Medieval changes. Middle Ages: the improvement of the climate coincides with a more intense cultural and economic level.

12th century - optimum medieval climate. A new increase (about half a degree) of the temperature coincides with the agricultural expansion; documents related with that tell us about it; something like that happens in Europe too. But, there is always a doubt: were the causes climatic or cultural?

Expansion of the monasteries and colonization of new lands.

At the end of the Middle Ages the Black Death razed Europe and that could be related to a climatic change.

15th century. Plague and famine related to persistent rainfall. In Galicia people say that "famine comes swimming". When the base of the nourishment was the cereals of winter the rain could reduce the harvest.

Little Ice Age - from the Middle Ages to the end of 18th century. The height of snow above the sea level was lower (600m) than nowadays (900m) but, there are not many facts to clarify this period in Galicia, although there were changes in the landscape because of human actions; the human impact was very clear becoming the minimum in forests at the beginning of the 19th century.

The increase. The temperature was growing at the end of 19th century. Some cooling was detected but, after that, it continued growing with some inflexions like in the period of the Spanish civil war (1936-1939). Diaz Fierros and Perez Alberti say that It's in the Industrial Age when the real problem starts (climatic change). The observatory of La Coruha verifies an increase of the temperature around one degree or one degree and a half from 1865, variation that had never been seeing in history.

The new change. With the present variation we wait for an increase within 2-4 degrees and a decrease of the rainfall among 20% and 30% in summer; and in winter a weak increase in temperature and rainfall. The tendency is not going to change much, but we can differentiate the effects in the coastal zones and in the middle country, or in the northern zone and in the southern one: it's going to be outstanding in the south and in the middle parts. In the coastal zone equivalence is difficult to find because the sea has an effect of complete equalization. One way or another an increasing of the sea level (about half a metre maximum) is foreseeable, which threatens to get a specific effect in this area, mainly in the lowlands and in the coastal marshes. The bet is done, it remains to be seen if we'll be able to change things or if, in the future, people will analyse again how our evolution has conditioned the climate.

THE CLIMATE CHANGE IN FINLAND

(The text was prepared by Finnish participants of EFW 2007 from the Kainuu Region)

Finland has series of measurements of climate and weather for over 100 years almost all over the country. That is why we have a lot of information of our climate history (Figure 1). Because Finland is a long country in south-north direction we have great differences in climate and weather between regions. Finland is in between oceanic and continental climates and that causes many of the changes in our weather. For example we have hot Siberian climate in south-east of Finland at the end of the summer. The average temperature has risen since 1850. The springs have become warmer since 1950 and autumns have got colder. There are some signals that we have more clouds nowadays. It means that we get less solar radiation. The clouds also keep daily average temperature more even. The measurements do not show that we would have less snow than earlier.

 Rainfall in Finland has remark-able natural differences between regions and time periods. That is why we can not say what is normal for nature and what is the result of the climate change. The amount of rainfall has risen a little bit in the last 100 years and timing of rainfall has moved from spring and winter to summer. Autumns are pretty dry nowadays.
We think that some parts of the climate change are natural but human has made it faster by his actions like polluting air with greenhouse gases from fossil fuels for example. In Finland 85 per cent of our carbon dioxide CO₂ emissions are from industry, warming of houses and traffic. Chlorofluorocarbons CFC's were forbidden in Finland in 1995.

The forecasts of different climatic models give conflicting results for Finland. The most uncertain thing might be the future of the Gulf Stream. If it gets weaker we would get a new Ice Age in Finland. Someone says that the warming caused by greenhouse gases compensates the coldness caused by a weaker Gulf Stream. Some simulations give a result where the average temperature in Finland would rise 34°C in winter and more than 2°C in summer (Figure 2). Someone also forecasts that the gap between oceanic and continental climates will get even wider.

Forecasting of rainfall amounts is even more complicated than forecasting of temperatures. In the whole of Northern Europe it is more probable that an amount of rainfall rises than decreases.

In Finland there are three scenarios that have been formulated from information about changes in radiation balance, Earth's average temperature and state of oceans. Behind these changes are emissions of greenhouse gases and other pollution. The three scenarios are low, average andhigh scenarios.

According to the average scenario the average temperature in Finland will rise faster than the average temperature of Earth. Our winters average temperature will rise more than the average temperature of our summers. Rainfall in winter will probably rise but increase in rainfall in summer is uncertain. An amount of rainfall will rise because of heavier rain. It do e s not me an that we would have more rainy days.

As you might already know we Finns have long distances between places like home and school. That is why we have a lot of cars even though we want to decline use of fossil fuels.

Private car driving is causing problem caused by even bigger carbon dioxide emissions. We have some public transport in Finland, but it is centred in cities. When the major part of Finns have long distances, it is understandable that busses will not visit every crossroad. If they did, the usual number would be only a few passengers, and that does not make a big matter comparing with private driving, when it comes to climate change. Because in Finland it is many times necessary to go by car, it would be more effective to develop fuels which are not causing such huge harm to environment. For example in Iceland there are some busses working with thermal gases from hot geysers.

Of course in big places, where air conditions are worse and distances smaller, limiting private driving is a good idea. Structure of cities could be designed so that it is more attempting to go by bicycle or walk than nowadays. People living in a same neighbourhood and going to work at the same time, can use "share-a-ride"- system, and some cars can stay in the garage even one day a week.

Government of Finland is having a debate of rising taxes of diesel to make public transport more popular. The problem is that remote places without regular bus traffic, like Kainuu, has not been noticed enough. Commuters here often have jobs in other provinces, when car driving is necessary. Usually people drive a lot and have diesel-cars because they use less fuel petrol-cars do.

Another notable thing is that our tree species will move up north if the climate gets warmer. We are researching how the nature will tolerate this change..

WFigure 2. If the concentration of CO₂ doubles this is how climate of Northern Europe changes.

On the left is situation in winter and in the right is situation in summer.

 (Source: Ilmastonmuutos ja Suomi, Helsinki University Press 1996)

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