How do we know that our climate is changing?

Credit: Pixabay

In order to be sure that our climate has changed we need to know what it was like in the past

In recent years there’s been a greater emphasis placed on observing the climate, due to the detrimental effect that its change is having on our environment. But that’s only in recent years, and prior to this there will have been little, if any, observation being conducted on the climate. So how can we be sure that it is in fact changing?

Well it’s lucky for us that some forward-backward thinkers found a way to do it; actually they found quite a few ways.

Due to the interest in conserving our planet and the new technologies available, scientists observing the climate now have an inventory of equipment with which to accurately measure and observe our present climate. There are acronyms like SQUID (Superconducting Quantum Interface Device) and SST (sea-surface temperature) being banded around.  Specialised facilities, organisations and even satellites are all closely monitoring parameters on land, at sea and in the atmosphere. But when it comes to collecting climate data from the past (300 years previously) things aren’t quite so simple; a little initiative is necessary, shall we say.

The growth of tree rings are largely affected by temperature and rainfall. We can therefore use growth rate to broadly estimate changes to rainfall or temperature depending on the preferences of the tree. The only problem with this method is that growth is affected by a range of climatic factors so it can be difficult to distinguish between each. This method can also be used with coral as they too have seasonal growth rings that are affected by temperature (faster growth in warmer waters).

The examination of ice cores can be used to reveal air temperatures. By taking samples of ice scientists can examine air bubbles that have become trapped within the layers of snow. It is these air bubbles that show not only temperature but also precipitation, dust transportation and volcanic fall out.

Ocean sediments are made of fossil shells, which accumulate on the seabed as organisms die. A sample of these sediments can be collected using a steel tube, which allow fossils to remain in their chronological order of formation. Analysis reveals what species inhabited the different layers and from that it’s possible to estimate if the water was warm/ cold by the preference and abundance of the species.

Pollen records date back to the Devonian era and provide a unique and unusual insight into our past climate. Pollen is the powder that contains the microgametophytes or the ‘sperm’ of seed plants. Its can remain perfectly preserved during fossilisation as it is protection by its outer sheath, known as the sporopollenin. Even in a fossilised state the tiny pollen grains are identifiable thanks to their distinctive morphology. The abundance and distribution of pollen can be used to estimate temperatures, depending on the plants preferences.

Although there are data gaps and inaccuracies associated with these ‘indirect’ methods of climate measurement, they’re important in giving us something to compare current data with. In some cases this data can be combined with information collected from modern equipment, like Stevenson shelters, weather bouys and satellites.

In order to better estimate how our climate might change in the future, it’s important that we understand changes that have occurred in the past.

GME: Genetically Modified Europe? Not likely

© Kathryn Darvill Photography

They’re key in the battle against pesticides, integral to the future of edible pharmaceuticals and might provide an answer to the world’s growing problem of human overpopulation. The potential of genetically modified (GM) crops is vast, but it seems that the European Union (EU) needs more convincing before it jumps on the genetically modified bandwagon.

There are just two GM crops that have previously been approved for cultivation by EU commission and it seems there might be, just might be room for another. Later this month the EU will vote to decide if a licence should be granted for the growth of a GM variety of maize. If approved, the insect-resistant maize will be the first GM crop authorised by the EU for 15 years. A feat which Environment minister, Owen Paterson is not proud of.

Speaking at the Oxford Farming Conference held on January 6th, Mr Paterson expressed his frustration with EU’s insistence against GM crops: “the longer that Europe continues to close its doors to GM, the greater the risk that the rest of the world will bypass us altogether”. Mr Paterson, who advocates the use of GM crops to be both safe and necessary, warned that Europe is in danger of “becoming the Museum of World Farming as innovative companies make decisions to invest and develop new technologies in other markets”.

If Europe’s past experiences with the GM industry are anything to go by then it seems Mr Paterson might be fighting a losing battle. In 2012 the GM company BASF abandoned its attempts to break into the European market and announced plans to focus on building business relations in the Americas and Asia. BASF’s product, the GM Amflora Potato plant was intended for industrial application; the plant had been modified to produce amylopectin, a starch particularly useful in papermaking. Even with official approval from the EU the plant faced widespread disapproval.

The case for the Amflora plant was exacerbated on December 13th 2013, when Europe’s General Court invalidated a decision to sell the crop on the European market. The second-highest court gave the ruling following a failure to correctly submit a European Food Safety Authority report on the Amflora plant. Although the plant had not been sold in Europe since 2012 the decision moves Europe one-step further from Mr Paterson’s ideal.