UK Average rainfall totals

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Moses Woods
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1 Qu: What effect has anthropogenic use of fossil fuels had on the carbon cycle and other earth systems? AIM: To be able to outline changes in ecosystems, the hydrological cycle and climate resulting from atmospheric carbon fluxes. ST: This area of Spain was undergoing an unusually severe drought in How has the carbon cycle been altered in this instance and can you identify a positive feedback loop? 1

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3 Correct so far. 3

4 200 UK Average rainfall totals Look how defined this change is was the wettest summer on record until and then winter 2013/14 was wettest ever. Task: Mind Map How could this influence the Hydrological Cycle? 4

5 The Atlantic Thermohaline circulation may weaken altering ocean heat transfers. This will alter food webs and the weather of NW Europe. Plant changes and adaptions will lag behind that of animals. Pests and diseases of warmer climates are affecting plants of colder climates. River regimes in the Himilayas will alter due to receding glaciers and less summer snow melt keeping them full. Sensitive flora and fauna species could face extinction as they struggle to cope with change.eg. Rainbow trout and polar bears. The Artic temperature has gone up more than twice the global average over the last 200 years indicating that some areas are more prone to rapid change than others. Drying soils are prone to blow away increasing amounts of exposed bedrock leading to surface run off and floods. The Sahel in Africa, South Africa and Mediterranean countries are getting drier with droughts more common. Flash floods and more intense rainfall events are increasing at mid-latitudes (UK) as warmer air holds more moisture. The intensity and frequency of tropical storms and hurricanes is increasing as a result of more heat and water vapour in the atmosphere around the tropics. Arctic and Antartic icesheets are showing signs of breaking up and thinning. Less sunlight will be reflected by the emerging darker sea or land surfaces. As CO2 is dissolved into the oceans they are becoming more acidic. Coral reefs are an example of a biome that cannot cope with such changes and are 'bleaching' (dieing) Thermal expansion of the oceans is creating sea level rises leading to increased erosion of estuarine habitats. The thawing of permafrost areas is increasing river discharges in Tundra regions, disruption fish spawning cycles. In general biodiversity is moving poleward as it gets warmer. eg. Oak trees are seeding in areas of Norway where once it was too cold. Unpredictable temperature and rainfall patterns are stressing habitats in equatorial and polar regions. A Colour code the above statements for Climate, Ecosystems and the Hydrological Cycle. Remember there may be some cross over. B For at least 2 statements, outline how they could trigger a positive feedback loop. C Can you find a negative feedback loop anywhere? (where systems respond to decelerate a process to regain equilibrium) 5

6 Some UK examples. Take notes on the following. Disc 2: Episode 8: 3:30 12:15 = Seasonal changes from daffodils to Blue Tits and effect on food chain Note that not all effects may be negative! Disc 2: Episode 8: 27:00 31:40 = Increase in severe weather and coastal erosion (synopticity) 6

Coral Bleaching Impacts on a major global carbon sink. http://www.bbc.co.uk/news/world australia 38127320 When the coral dies, the entire ecosystem around it transforms.

7 Coral Bleaching Impacts on a major global carbon sink. australia When the coral dies, the entire ecosystem around it transforms. Fish that feed on the coral, use it as shelter, or nibble on the algae that grows among it die or move away. The bigger fish that feed on those fish disappear too. But the cascading effects don t stop there. Birds that eat fish lose their energy source, and island plants that thrive on bird droppings can be depleted. And, of course, people who rely on reefs for food, income or shelter from waves some half a billion people worldwide lose their vital resource. As sea temperatures rise more Carbon di Oxide is dissolved into the oceans increasing their acidity. Coral is calcium carbonate which weakens and dissolves in acid conditions. 7

Warmer water temperatures can result in coral bleaching. When water is too warm, corals will expel the algae (zooxanthellae) living in their tissues causing the coral to turn completely white.

8 Warmer water temperatures can result in coral bleaching. When water is too warm, corals will expel the algae (zooxanthellae) living in their tissues causing the coral to turn completely white. This is called coral bleaching. When a coral bleaches, it is not dead. Corals can survive a bleaching event, but they are under more stress and are subject to mortality. In 2005, the U.S. lost half of its coral reefs in the Caribbean in one year due to a massive bleaching event. The warm waters centered around the northern Antilles near the Virgin Islands and Puerto Rico expanded southward. As reefs die carbon sesquestration rates drop and if they start dissolving the role of reefs as a sink will reverse and they will become a carbon source in the long run. Task: Use this slide to annotate your copy of the Great Barrier Reef, Eastern Australia. Outline how and why it is happening, impact on ecosystems and impact on the carbon cycle. 8

9 Can you name and locate examples of ecosystems, climate and the hydrological cycle that are being impacted by global warming. Are you able to explain how carbon stores and fluxes are changing at local and global scales? Anstey ponders the above questions 9

10 Extra Reading 10

11 Look around the world and the effects of climate change are there for all to see. Glaciers are on the retreat in the Rockies, Andes, Alps and Himalayas. The Greenland ice sheet is shrinking by as much as 60 cubic miles a year. And the area covered by Arctic sea ice at the end of this summer was the fourth lowest on record. In a warmer world snow and ice is turning to slush. Average global temperature is now one degree Celsius higher than it was in Before the industrial revolution, levels in the atmosphere were around 280 parts per million. Now they've shot through 400. That's the highest they've been in at least three million years. And the overwhelming majority of scientists believe it's human activity that is to blame. Natural variation in the climate and changes in the activity of the sun simply cannot account for the rise in carbon dioxide or global temperature. So is Prince Charles right to say "nature's bank is going bust"? Well certainly ecosystems are under pressure. On the Great Barrier Reef, coral bleaching caused by rising sea temperatures is becoming more common. In the Arctic polar bear numbers are dwindling because of the disappearing sea ice. And humans are feeling the effects of climate change too. This year Vanuatu was hit by the most powerful cyclone ever recorded in the South Pacific. California is suffering its worst drought in several centuries. And even in the UK, where we are blessed with a comparatively benign climate, winter floods have become more common. Around the world climate change is making wild weather more likely and more extreme. The majority of scientists agree that two degrees is the safe limit for global warming. And that's the target the UN climate change meeting in Paris is aiming for. So far carbon reduction pledges made by nearly 150 countries ahead of the conference will limit future global temperature rise to 2.7 degrees if they are enforced. That's better than the five degree rise predicted if we carry on as we are. But the sea level would still rise by more than a metre. Corn and wheat yields would drop by around a quarter. And heatwaves would be the norm for European summers. Much more needs to be done to stabilise the climate. By the end of the century the world will have to be using 100% carbon free energy. And some way will need to be found of sucking greenhouse gases out of the atmosphere. Nature's bank as Prince Charles calls it isn't yet bust, but it's heavily in debt. It needs world leaders to agree an environmental bailout. 11

The IPCC has not evaluated how the suitability index will change due to climate change rainfall projections. Discussions are underway to launch such an effort.

12 The IPCC has not evaluated how the suitability index will change due to climate change rainfall projections. Discussions are underway to launch such an effort. However, we can at least make a simplistic estimate of the future of global agricultural production based on projected changes in precipitation. Of the seven major regions with a high or moderate suitability index (Figure 1), we can see that: 1) The central U.S. will likely experience a modest decrease, particularly in the Great Plains, 2) Mexico and Central America will likely experience a significant decrease. This decline in precipitation is a feature of all global climate models. Because of the magnitude of this impact on our neighbors to the south, our U.S. national policy makers should monitor climate change over this region through the coming years. 3) Brazil, Uruguay, and Argentina might see an increase in rainfall that likely will be beneficial, 4) Southern and eastern Europe likely will see a substantial decrease, 5) Central Africa likely will see an increase and southern Africa a decrease, 6) India probably will experience an increase. 7) China and East Asia will probably experience an increase. However, the likelihood of extreme increases in precipitation in these areas may be detrimental to agricultural production. 8) Australia is projected to see an increase in the east and a decrease in the west. Regions with a long history of cereal production, such as Australia, are already facing new challenges (Reuters, 2008). Six continuous years of drought have reduced Australia s rice crop by 98 percent and has shut down processing plants (Bradsher, 2008). 12

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As the lower atmosphere becomes warmer, evaporation rates will increase, resulting in an increase in the amount of moisture circulating throughout the troposphere (lower atmosphere).

14 As the lower atmosphere becomes warmer, evaporation rates will increase, resulting in an increase in the amount of moisture circulating throughout the troposphere (lower atmosphere). An observed consequence of higher water vapor concentrations is the increased frequency of intense precipitation events, mainly over land areas. Furthermore, because of warmer temperatures, more precipitation is falling as rain rather than snow. In parts of the Northern Hemisphere, an earlier arrival of spring like conditions is leading to earlier peaks in snowmelt and resulting river flows. As a consequence, seasons with the highest water demand, typically summer and fall, are being impacted by a reduced availability of fresh water. 14

15 Attachments Coral Reef Bleaching

What is the IPCC? Intergovernmental Panel on Climate Change

IPCC WG1 FAQ What is the IPCC? Intergovernmental Panel on Climate Change The IPCC is a scientific intergovernmental body set up by the World Meteorological Organization (WMO) and by the United Nations