Atmosphere

Coastal flooding around the UK coastline

Coastal floods, driven by extreme sea levels, are a major hazard both nationally and globally, with wide-ranging social, economic and environmental impacts. Nationally, it is estimate that £150 billion of assets and 4 million people are currently at risk from coastal flooding in the UK [1]. Coastal flooding is rated as the second highest risk for causing civil emergency in the UK, after pandemic influenza [2]. Combined with fluvial flooding, it is responsible for at least £0.25bn in annual economic damages [3]. Coastal flooding is a growing threat due to accelerating average sea-level rise and possible changes in storminess associated with climate change [4] as well...

Oxygen Isotopes in Speleothems

Stalactites and stalagmites (also called speleothems) are found in cave environments across the planet (see Figure 1). They form as water from the surface percolates into the ground and drips into the cave. Speleothems can be extremely sensitive to changes in climate and environmental conditions and they record these changes as variations in their chemistry. An excellent review of speleothem formation and their use for palaeoclimate reconstruction by Prof. Ian Fairchild can be found here, so this article focuses on the way that oxygen is stored in speleothems and how we can use this as a record of past climate conditions.   Why and how do we use oxygen isotopes? Oxygen...

In brief: the UN Climate Summit

This week, delegates from the UN met in New York to discuss global climate change and to develop strategies for tackling these issues.  What are the outcomes of their discussions? And what does this mean going forwards? #climate2014   The meeting in New York was the largest climate meeting since Copenhagen 2009, and 120 world leaders took part in discussions. As well as discussing issues surrounding climate change, the summit aimed to encourage member states of the UN to sign the global climate agreement, which will be announced next year in Paris.  The talks focused on eight areas: agriculture, cities, energy, financing, forests, industry, resilience,...

IPCC special: Future climate phenomena and regional climate change

The latest report of Working Group I of the Intergovernmental Panel on Climate Change (IPCC) combines new and better observations with improved models to provide a clearer and more definite picture of humanity’s influence on the climate system, and the paths we can choose for the future. The atmosphere continues to warm, with the last three decades each being warmer than the one before, and all three being warmer than any other decade since reliable observations began in the 1850s. Warming is seen almost everywhere on the Earth’s surface, and many observed changes are unprecedented on scales of decades to millennia. We also now have...

IPCC special: Long-term climate projections

Chapter 12 of the 5th Assessment Report of IPCC (Intergovernmental Panel on Climate Change) deals with future projections of climate change in the long-term. Long-term in this case means beyond the middle of the 21st century when the projections start to depend more strongly on the pathway or scenario of emissions of greenhouse gases, principally CO2. We rely extensively on computer models of the climate system for this as, obviously, there are no observations of the future. While computer models are not completely accurate in their ability to project future climate change, it is possible to use our understanding of the climate system to assess uncertainties...