Drought in Catalonia (Spain), floods in south-west Thessaly (Greece), fires and heat in Sicily (Italy). Unfortunately, reports like these have become the norm in the Mediterranean region. Extreme weather conditions are steadily increasing and are having a devastating impact, including on local agriculture. This affects not only fruit and wine, but also the beloved olive oil.
For the consumer, the effects can first be seen in the purchase price of olive oil. Whether in the supermarket, at the delicatessen or online - olive oil has become significantly more expensive everywhere in the last two years. At the same time, recent reports lead to the assumption that the quality of olive oil is declining at the same time. This can be seen, for example, in the article "So schmeckt Klimawandel" by Stiftung Warentest (issue 4, 2024), which took a closer look at the quality of various olive oils in German supermarkets.
Although the above-mentioned test report from Stiftung Warentest needs to be viewed in a more nuanced way, certain theses can be agreed with and it can be said across the board that climate change has an influence on the yield, quality and price of olive oil. We also explained these correlations in more detail in an interview with OliveOilTimes.
As climate change is becoming an increasingly pressing issue in our lives, we have decided to publish a more detailed article on the topic of "Climate change and its impact on olive oil". At the same time, we can bring our experience to this topic and provide context. At Protos Mediterranean Specialities, we have been importing the liquid gold from the Mediterranean region since 1995 and have learned a lot about this wonderful natural product and experienced a lot since then. From forest fires, which have destroyed entire olive groves, to various tricks used by oil millers around the olive product. So let's dive straight into the topic with the following question:
Unfortunately, there is no simple answer. Because, as is so often the case in life, complex issues cannot be answered with a simple "yes" or "no".
But a simple farmer's rule helps to create a foundation. As with wine, there are "good vintages" and "bad vintages" for olives, because the perfect harmony of several factors determines the yield on the one hand and the quality on the other. In other words, if the conditions are ideal, this logically has a positive effect on the olive harvest and consequently on the oil obtained from it. The question is therefore whether bad vintages are becoming more frequent as the general conditions deteriorate.
To answer this, we should take a look at the conditions that are ideal for the tree and the fruit. From flowering to fruiting, an olive tree needs sun, water and the right temperatures, and preferably no pests. All of this is directly and indirectly controlled by the climate. In detail, the ideal conditions for the olive tree are as follows:
A look at the world's largest olive oil producer - Spain - provides new insights. Around 350,000 farmers grow olives there. Almost 90 per cent of Spain's oil production comes from Andalusia, much of which is from the province of Jaén. For two years in a row (2022 & 2023), Andalusia had to contend with extreme climatic conditions. Too little rain in winter, the first heatwaves during flowering in April and May and exceptionally dry and hot summers caused headaches for local farmers and oil millers.
These weather conditions are also reflected in the yield. (see historical data from the International Olive Council here). Here we see that Spain in particular has recorded enormous declines since the 2018/2019 harvest. The comparison 2022/2023 to 2018/2019 shows a decline of 1010 [x1000t] olive oil. But if we look at Greece, we see that the harvest yield in 2022/2023 was relatively good compared to previous years. This means that not all Mediterranean countries are experiencing a decline in olive oil yields.
But "good" yield does not mean good quality
Although, generally speaking, the olive harvest in Greece was subject to fewer fluctuations in yield than in Spain, the effects of climatic changes can also be seen there. In Greece, the occurrence of olive fly populations in some growing areas, particularly in the Peloponnese and Crete, the two centres of the Greek olive oil industry, is a cause for concern. The olive fly (Bactrocera oleae) is a major pest that affects not only the yield but also the quality of the olives and therefore the olive oil. Below is a brief explanation of the olive fly.
The females of the olive fly lay their eggs in ripening olive fruit, where the newly hatched larvae feed on the fruit flesh. The larvae either pupate directly in the fruit or reach the ground to pupate. Larvae feeding causes several problems. On the one hand, of course, a lower yield. At the same time, the acid content in the infested fruit increases (due to the growth of microorganisms), which results in a lower value of the pressed oil. (For olive oil to be classed as grade 1 the acidity must be below 0.8%). At the same time, the fruit is also more susceptible to other pests and fruit rot.
Picture of olives infested by the olive fly
The increase in the population of the olive fly throughout the Mediterranean region is rightly causing headaches for olive growers and oil millers. At the same time, this pest is present in almost the entire Mediterranean region. We can therefore see that climate change has only improved conditions for pests. This change, combined with extreme weather conditions, affects the yield and quality of olive oil accordingly.As already explained, olive trees are sensitive to extreme temperature changes. Unusually high temperatures in winter and spring and prolonged heat waves in summer can affect the flowering period and fruit development. This leads to a lower yield and can negatively affect the quality of the olives and therefore the olive oil.
As already mentioned, irregular rainfall or periods of drought reduce the yield and also the quality, as the fat content of the olive is reduced. Extreme sporadic rainfall can sometimes lead to the erosion of the soil as well as important nutrients and minerals. At the same time, too much water can increase the risk of diseases (rot) and pests. Olive trees need a balanced water supply
As temperatures rise and climatic conditions change, the risk of pest infestation and disease also increases. For example, the olive fly, a well-known pest, multiplies more quickly in warmer temperatures and can cause considerable damage to olives.
Of course, there are other consequences and risks of climate change in relation to olive production, such as changes in the chemical composition of the olive fruit, etc., but this is beyond the scope of this article.
One thing is clear, climate change poses a significant challenge for the olive oil industry. Although the consequences may differ from region to region, negative changes in quality and, above all, in yield can be recognised. Essential changes are therefore not only important, but a must in order to ensure the quality and availability of high-quality olive oil.
Agricultural areas with more biodiversity in terms of flora and fauna are more resistant to direct and indirect climatic changes. This thesis is supported by numerous studies and should also be focussed on in the olive oil industry. In other words, organic farming or controlled organic cultivation should be the foundation of the future. In addition, biodiversity in olive groves must be significantly increased so that nature and agriculture mutually promote each other. The "Olive Alive Project" offers an interesting approach to this, which can be summarised as follows.
Restoring the natural richness of olive groves increases the profitability of producers, as flora and fauna work for the benefit of the olive grove. When ecosystem services are recovered through biodiversity, this has a direct positive impact on fertile soils, greater water retention, lower erosion rates and better natural pest control. The olive grove is thus more resistant to heat and drought, changing rainfall patterns and pests.
Another approach concerns the selection of heat- and drought-resistant olive varieties. Studies are already being carried out in this area. A research team in Israel has already been working on this topic. Read more here.
To summarise, we can say that climate change has direct and indirect effects on olive production and olive oil production. As a direct importer of olive oil from the Mediterranean region, we can already recognise certain trends: On the one hand, the acidity of many extra virgin olive oils has increased by about 0.1 to 0.2 % (whether from Spain, Greece or Italy) and the polyphenol content has decreased. These are two decisive quality factors for (extra virgin) olive oil. At the same time, the availability of olive oil and specifically extra virgin olive oil has decreased. This is also reflected in the fact that more virgin olive oils (grade 2) are available. Some producers are also consciously opting for extra virgin olive oil of the highest quality in addition to extra virgin olive oil.
One example of this is Mani Bläuel with its 100% virgin organic olive oil. Due to the consequences of climate change, the oil miller and his olive growers have been looking for a sustainable solution to ensure that farmers can continue to buy olives in the long term, regardless of the acidity of the olives. Organic virgin olive oil is produced in the same way as extra virgin olive oil. It is also cold-pressed and consists of 100% Koroneiki olives. However, the acidity is slightly above 0.8%, which means that it no longer falls into grade 1. However, there is no discernible difference in flavour (for the average consumer).
On the one hand, we have to reckon with regional shifts. Traditional olive-growing regions that do not manage to adapt their cultivation and care methods to the weather conditions in a sustainable way will become unproductive in the long term. At the same time, new regions that were previously unsuitable for olive growing will suddenly offer favourable conditions for olive cultivation in the future. We therefore expect a shift in production in the long term. It is quite possible that Andalusia in Spain, for example, will lose its leading role in the olive oil industry (if no sustainable strategies are implemented).
At Protos Mediterranean Specialities, we remain committed to offering only high-quality olive oils from Greece, Italy and Spain. We work closely with our producers to ensure that, despite the challenges of climate change, the quality of our products meets the highest standards.
