Global warming and climate change

Answers to popular questions on global warming and climate change, sustainability and what you can do to help.

Classroom resource

We’ve consulted experts and gathered responses to common questions from young minds about climate change, sustainability and how outdoor learning can help.
This interactive poster has been designed to support learning and teaching as well as create an eye-catching classroom display. Support pupils to learn independently and find the answers by scanning the QR code on each poster.
Any of these materials can be paired with one of our talks from the RSE schools talks programme, and are ideal for use with pupils in broad general education (BGE).
 
  • I can explain some of the processes which contribute to climate change and discuss the possible impact of atmospheric change on the survival of living things. SCN 3-05b
  • I can identify the possible consequences of an environmental issue and make informed suggestions about ways to manage the impact. SOC 3-08a
  • I can investigate the climate, physical features and living things of a natural environment different from my own and explain their interrelationship. SOC 3-10a
  • I can investigate the relationship between climate and weather to be able to understand the causes of weather patterns within a selected climate zone. SOC 3-12a

ANSWERS PROVIDED BY

Dr Roger Scrutton, Honorary Research Fellow, Moray House School of Education, University of Edinburgh Dr Scrutton’s academic journey began in 1974 at Edinburgh University, where he specialised in geology and geophysics. Retiring from his role as a Reader in Geophysics at the School of Geosciences, he embraced his passion for outdoor pursuits. Now an Honorary Research Fellow at Moray House School of Education, University of Edinburgh, Dr Scrutton explores the benefits of residential outdoor education. He chairs the Outdoor Pursuits Group within the Scottish Sports Association and is a Trustee for the Orienteering Foundation and the Friends of Benmore Outdoor Centre. As a member of the Scottish Adventure Activities Forum and the Scottish Outdoor Recreation Alliance, Dr Scrutton remains dedicated to promoting outdoor education and activities.


Is global warming something new? 

The answer is “yes and no”. All parts of the earth’s surface have experienced warm periods and cold periods (relative to what they have today) over geological time (that is, over 4 billion years) as a result of the changing distribution of landmasses and oceans, changing ocean currents, the amount of volcanic activity, the amount of tree cover and small shifts in our orbit round the sun. For example, about 2 million years ago, northern Europe was in the grip of an ice age. We are still in this ice age but at present experiencing an inter-glacial period, ice cover having retreated from Scotland about 10,000 years ago: it is difficult to predict when ice might return, but perhaps in several thousand years’ time. The global warming period we are in now is very different in that it is happening quickly (since the 19th Century), and it is global, i.e. affecting all areas of the earth’s surface, and it is in the presence of significant human activity. We have enough data, computer power, knowledge of the way society has developed industrially, and an understanding of environmental science to show that it is caused by human behaviour. The root cause of global warming is our overuse of fossil fuels – coal, oil, and natural gas – which have been used by humans as an energy source for centuries but have been increasingly used since the beginning of the 19th Century when the invention of coal-fired steam engines led to the Industrial Revolution, increased carbon dioxide emissions, the creation of a greenhouse effect in earth’s atmosphere and then global warming. However, other human activities have contributed, such as loss of forest cover and certain agricultural practices. Despite good evidence that global warming is happening as a result of human activity, there are some people who do not believe it is happening at all or not happening because of human activity. One of their strongest arguments is that earth has always experienced climate swings, but we have not had human beings on earth through these climate swings. When human activities, e.g. burning fossil fuels, are included in computer models of the earth’s surface temperature, it is very difficult to say that the current swing is not due to human activity. Consequences of global warming are changing weather and climate patterns, rising sea level, biodiversity loss and their impact on different communities across the world.

The graph shows how the average global surface temperature increased rapidly from 1900 onwards by about 1.2oC (black line).  The difference between the green and red lines is what is calculated to be the contribution of human activity to global warming through the overuse of fossil fuels, which started in the early 1800s but took about 100 years to have a clear effect.

Is global warming real?

Despite good evidence that global warming is happening as a result of human activity, there are some people who do not believe it is happening at all or not happening because of human activity. Some who deny the presence of global warming do so for personal reasons or to protect their business interests, but for others for whom it is worrying or even stressful, it might be a myth or fake news. However, one of the strongest arguments of those with reservations is that Earth has always experienced climate swings, which is true, and some of these swings were nearly as rapid and global in nature as the current warming event. Having said that, we have not had human beings on Earth through these climate swings. When human activities, e.g. burning fossil fuels, are included in computer models of Earth’s surface temperature at the present day, it is very difficult to say that the current swing is not due to human activity.

An early pointer to the influence of humans is the regular measurement taken from ice cores and other sources of carbon dioxide gas in the atmosphere released by burning fossil fuels. This graph for the last 40,000 years shows how the CO2 concentration has shot up since about 1850.

Who or what is gaia?

The Gaia Hypothesis was put forward by James Lovelock and Lynn Margulis in 1972. In a nutshell, it proposed that the earth’s physical and biological systems are inextricably linked with one another to have a regulatory effect on the natural environment and provide life-sustaining conditions. Life has indeed been sustained on earth for millions of years, sometimes flourishing, sometimes exotic, and has become increasingly complex. All parts of the earth’s surface have experienced warm periods and cold periods, dry periods and wet periods (relative to what they have today) over geological time, but through all of this, life has been sustained. The current period of global warming due to human activity is anomalous in that it is a global phenomenon that is happening very quickly, thus upsetting the proposed regulatory effect and producing rapid climate change and biodiversity loss. However, in 1972, it was already clear that anomalous global warming was occurring. Also, Lovelock and Margulis received some criticism of their hypothesis in that it does not account for extreme events, such as Snowball Earth (most recently about 600 million years ago) and mass extinctions of organisms – we’ve had five – and, perhaps, nowadays, rapid global warming and biodiversity loss could lead to a sixth unless we act quickly to curtail global warming. Interestingly, Gaia was the Earth goddess in Greek mythology and the protector of life on earth. Gaia is increasingly popular as a girl’s name, perhaps in response to awareness of global change.

How long will it take to change from fossil fuels to renewable sources?

Fossil fuels – coal, oil, natural gas – have been used by humans as an energy source for centuries, but increasingly, since the beginning of the 19th century when the invention of coal-fired steam engines led to the Industrial Revolution, increased carbon dioxide emissions and then to global warming. Scotland was the first in the UK to have an oil industry, from 1847, extracting oil from oil shale in the West Lothian area. Strictly speaking, renewable sources have also been in use for centuries, e.g. the water wheel and windmills. However, from about 100 years ago, the various types of renewable energy we would recognise today were being developed on a large scale, e.g. hydroelectric power in Scotland. There followed a gradual adoption of the term ‘renewables’, so today, we recognise about a dozen different sources of renewable energy: solar, wind, nuclear, wave and tide, hydroelectric, geothermal, and so on. Fossil fuels are being phased out – coal mining ceased in Scotland in 2020 – but that must be at a rate that would meet gaps in our energy needs as we transition to renewables. Predictions of when we could generate enough renewable energy to replace all but a few natural gas power stations vary from 2030 to 2060, depending on the country and its government’s policies and technological advances in areas such as energy transmission and storage.

Why is our weather so wild these days?

We have always had sunny days, rainy days, windy days, foggy days, freezing days and scorching hot days – this is what we call the natural variability of the weather – but nowadays, these weathers are more intense. Is it because of climate change? Yes, it probably is, but it is only recently that scientists have been able to prove this. It seems that none of the extreme weather events affecting the UK have been attributed to climate change in a scientifically sound (statistically rigorous) way. Still, it is hard to ignore that every year, we break one weather record or another, e.g., the wettest winter, sunniest spring, hottest summer, and coldest winter (that’s always in Scotland!). It is important to remember that climate change (the year-on-year change in our climate) and severe weather (individual severe weather events) significantly impact biodiversity. Although the scientific work is challenging, there is a sound theory, Attribution Theory, that links our most extreme weather events to global warming, and the underlying reason is that with increasing temperatures at the earth’s surface, the air holds more moisture through evaporation from the oceans and more energy – two key ingredients of severe storms.

Should we be worried about rising sea levels?

Yes. The rising sea level is a global problem affecting all coastlines and is a big problem for low-lying countries. Some coastal areas in the UK will be flooded with significant habitation loss for people, birds, animals, farmland, and fisheries. Still, steeper coastlines, which are common around Scotland, should not see such inundation. The sea level is currently rising at 3.5-4.0 mm/yr. In some places around the UK, it is intended to allow the sea to flood low-lying land to create new habitats for wildlife; in areas where people are affected, relocation will be offered, and in other places, improved sea defences are envisaged. However, given our increasingly stormy weather, improved defences will have to cope with that, as well as the rise in sea level. The rise of sea level is potentially devastating for low-lying communities, such as populations living on coral atoll islands. International relocation is possible for these people, but they are reluctant to leave their homelands.