WATER AND CARBON CYCLE
IMPACTS ON CARBON STORE arctic tundra
Oil and gas exploitation on Alaska north slope has ad significant impacts on the permafrost and on local carbon cycles. Permafrost is a major carbon store in the tundra, and is highly sensitive to change in the thermal balance. In many areas this balance has been disrupted by the activities of oil and gas companies which have caused localised melting of the permafrost. The melting is associated with construction and operation of oil and gas installation, settlements and infrastructure diffusing heat directly into the environment and the removal of vegetation cover which insulated the permafrost. Permafrost melting release co2 and methane. On the North Slope, estimated losses from the permafrost vary from 7 to 40 million/tonnes/year, while ch4 losses range from 24,000 to 114,000 tonnes/year. In addition the oil spillages and gas flaring also increase the input of co2 into the atmosphere. In addition, other human activity such as industrial development which have led to changes in the local carbon cycle. For example, the destruction or degrading of tundra vegetation which takes away insulation for permafrost as well as reduces photosynthesis and the uptake of carbon dioxide from the atmosphere. In addition, the thawing of soil increases microbial activity, decomposition and the emissions of carbon dioxide. Moreover the arctic tundra is very slow growing meaning that the regeneration and recovery of the vegetation will take decades to take place.
What are the three types of inputs into a drainage basin?
Orographic which is where air masses rise over mountains causing it to condense and rain. Frontal where two air masses meet at an area of low pressure creating rain. Convectional rainfall caused by water turning into vapour due to sole radiation.
PHYSICAL FACTORS- arctic tundra water cycle
Physical factors also have a great influence the water cycle in the arctic tundra. flows of water in the tundra are influenced by temperature, relief and rock permeability. Average temperatures are well below freezing for most of the year so that water is stored as ground ice in the permafrost layer. During the short the short summer the shallow active layer thaws and liquid water flows on the surface. Meltwater forms millions of pools and shallow lakes which stud the tundra landscape. Drainage is also poor; water cannot infiltrate the soil because of the permafrost at dept. in winter, sub-zero temperatures prevent evapotranspiration. However, in summer some evapotranspiration occurs from standing water, saturated soils and vegetation. Humidity is low all year round and precipitation is sparse. Moreover, permeability is low owing to the permafrost and the crystalline rocks which dominate the geology of the tundra in Arctic and sub-arctic Canada. the ancient rock surface which underlies the tundra has been reduced gently undulating plain by hundreds of million years of erosion and weathering. Minimal relief and chaotic glacial deposes impede drainage and contribute to water logging during the summer months. Therefore, physical factors also have a large impact on the water cycle in the tundra just as well as human factors.
How does relief effect the drainage basin?
Steeper slopes means faster runoff and shorter times for water storage.
What is a water store?
Stores if water which could be either in the form of Oceans, lakes, aquifer and the cryosphere (glaciers)
international agreements
The international agreements are a strategy to help reduce carbon emissions on a global scale. Until recently the only significant international agreements to tackle climate change has been the Kyoto Protocol (1997). Under Kyoto most rich countries agreed to legally binding reductions in their co2 emissions, though controversy, developing countries and some of the biggest polluters were exempted. However, then several rich countries like the US and Australia refuse to ratify the treaty. Kyoto the expired in 2012. After more negotiations a new agreement was formed called the Paris agreement. It aims to reduce global co2 emissions below 60 per cent of 2010 levels by 2050 and keep global warming below 2 degrees Celsius. However. Countries will set their own voluntary targets. These are not legally binding and a timetable for implementing them has yet to agreed. Meanwhile rich countries will transfer significant fund and technology to assist poorer countries, so they are able to accomplish their targets. However, the agreement caused some conflict because the developing countries which were very large emitters (china and India) and they believed it was the richer countries responsibility to reduce the emissions not theirs. This is because countries such as china and India are still relatively poor, and industrialisation focused on fossil fuels helps their country develop. Moreover, historically Europe and north America through their own industrialisation periods and development could be argues the ones to be blamed for global warming. In additional the agreements also where hard to schedule and got delayed several times and therefore wasn't that affective. The international agreements are making effort to try reverse the impacts of carbon emissions from global warming and how it is on a global scale however there are so flaws in the agreement for example it will take a while before we are able to see an actually change and it can cause conflict between countries.
What are the outputs of a drainage basin?
- evaporation, water turning into water vapour - Transpiration, water leaves through holes in a plant - Channel flow, water that is leaving through a river.
What are the flows of a drainage basin?
-interception, when planet capture water in their leaves -Infiltration, when water enters the soil -direct run-off, when water flows across the ground because the ground in impermeable. - Saturated overland flow which is when the ground is full of water so result in runoff -Through flow the horizontal flow of water through soil/rock layers -Percolation, the vertical flow of water in-between rock. -Ground water flow, water which flows horizontally once it has reached the water table.
What is the total global water supply?
96.5% of earths water is in oceans, 2.5% is freshwater and 1% is in other saline water sources.
What is dynamic equilibrium?
A state at which the inputs and outputs are different. If an element in the system changes this will upset the equilibrium; this is called feedback.
afforestation schemes
Afforestation is a management's strategy which attempts to reverse climate change impacts on both the water and carbon cycle at a regional scale. Afforestation involves planting trees in deforested areas as they act as a carbon sink. Afforestation can help reduce atmospheric carbon dioxide levels in the medium and long term and combat climate change. it also has other benefits such as reducing flood risks and soil erosion and increasing biodiversity. Forestry schemes also help protect forest form deforestation as they play a crucial part in the water cycle. It helps increase interception from the tree canopy and helps with the loss of water through transpiration. Vegetation cover also influences soils moisture through inception and transpiration. The UNs reducing emissions from deforestation and forest degradation (REDD) programme and the World Bank's Forest carbon partnership Facility (FCPF) fund over 50 partner countries in Africa, Asia-pacific and south America. REDD afforestation scheme aimed to plant around 20 million new trees. However, many of these trees which are planted are monoculture meaning one species which usually means they are only used for financial gain instead by the using them for paper etc. moreover it will take decades to see an actual change in both of the cycles the trees must grow beforehand.
ARTIC TUNDRA
Arctic tundra is a very cold, windy, and treeless biome that's snow-covered for much of the year. It's found in the northern hemisphere, encircling the north pole and extending south across parts of Alaska, Canada, Russia, Greenland, Iceland, and Scandinavia, to the coniferous forests of the taiga. The arctic tundra occupies some 8 million km2 in Northern Canada, Alaska and Siberia. Climate conditions in the tundra become more extreme with latitude. For eight or nine month the tundra has a negative heat balance with average monthly temperatures below freezing. As a result, the ground is permanently frozen with only the top metre or so thawing during the Arctic summer. Permafrost unlies much of the tundra and is an important feature of the region's water cycle. The global water cycle consists of three main stores: the atmosphere, oceans and land. The oceans are by far the biggest store and the atmosphere is the smallest. Water moves between these stores by precipitation, evaporation, run-off and groundwater flow. The human factors such as local settlements and oil extraction impact the water cycle in the arctic tundra dramatically. There are also physical factors which can significantly affect the water cycle; temperature, relief and rock permeability. There is already low annual precipitation (50-350mm) with most precipitation falling as snow. There are small stores of moisture in the atmosphere owing to low temperature which reduce absolute humidity. There is also limited transpiration due to the lack of vegetation and low rates of evaporation as much of the suns energy in the summer months are focused on melting the snow. The permafrost is a barrier to infiltration, percolation, recharge and ground water flow, Moreover, the extensive wetlands, ponds and lakes on the tundra during summer which means there is a temporary sore of liquid water is due to permafrost which impedes drainage. The changes to the water cycle due to human and physical factors are evident in my case study; the Arctic Tundra.
Carbon cycle amazon deforestation
Deforestation is the main human impact on a tropical rainforest. Deforestation in Amazonia averaged around 17500 km2/year between 1970 and 2013. Since 1970 almost one-fifth of the primary forest has been destroyed or degraded, though in recent years rates of deforestation have slowed. The above ground biomass in the rainforest is approximately 180 tonnes/ha. Most of the remaining carbon is found in the soil as roots and dead organic material. Rainforest trees are firstly very important as without them vegetation in soils becomes poor and reduces the flow of carbon from the soil to the atmosphere. Deforestation exhausts the carbon biomass store. Croplands and pasture contain only small amounts of carbon compare to the forest trees. For example, the biomass of grasslands in areas of former rainforest is 16.2 tonnes/ha and for soya cultivation it is just 2.7 tonnes/ha. At the same time deforestation drastically, reduces inputs of organic material to the soil. Soils depleted of carbon and exposed to strong sunlight support fewer decomposer organisms, therefore reducing the flow of carbon from the soil to the atmosphere.
Human activities which help the carbon and water cycles in the arctic tundra
Development on the North Slope has often involved the deliberate destruction of the permafrost. Today the emphasis is on protecting the permafrost thus minimising disruption to the water and carbon cycles in the arctic tundra. Examples of human activities which help protect the permafrost are: insulated ice and gravel pads, building and pipelines elevated on piles and drilling lateral beyond drilling platforms. Insulated ice and gravel pads can be placed on roads and other infrastructural features will help protect the permafrost from melting. Constructing building, oil/gas pipelines and other infrastructure on piles allows cold air to circulate beneath these structures. This provides insulation against heat-generating buildings, pipework etc which would otherwise melt the permafrost. New drilling techniques allow oil and gas to be accepted several kilometres from the drilling site. With fewer sites needed for drilling rigs, the impact on vegetation and the permafrost due to construction is greatly reduced.
drainage basin management strategy
Drainage basin management is a local management strategy which helps the climate change impact on the water cycle. The management of resources is most effective at the drainage basin scale. At this scale is considered the most effective. At this scale it is feasible to adopt an integrated or holistic management to approach to accommodate the often-conflicting demands of different water users. Agriculture, industry, domestic use, wildlife and recreation and leisure generate harsh demands that impact on water quality, river flow, groundwater levels and wildlife. Specific Targets including run-off, surface water storage and groundwater. Rapid runoff is controlled by reforestation programmes in upland catchments, reducing artificial drainage and extending permeable surfaces in urban areas. Surface water storage is improved by conserving and restoring wetlands, including temporally storage on floodplains. Groundwater levels are maintained by limited abstraction and by artificial recharge, where water is injected into aquifers through boreholes. However, this is only on a local scale, so this means it doesn't have much impact on the long term.
importants of trees carbon cycle
Forest tress dominate the biomass of the amazon basin and are the prinisple carbon store. They hold approximately 100 billion tonnes of carbon. They also are able to absorb up to 2.4 billion tonnes per year and release around 1.7 billion tonnes via decomposition. The rainforest is majorly important at is it one of the largest global sinks. 60 percent of rainforest carbon is stored in the above ground biomass of tree stems, branches and leaves. The remainder is below ground, mainly as roots and soil organic matter. Additionally, without the trees photosynthesis would not be able to occur. High temperature, high rainfall, and intense sunlight stimulate primary production. NPP average about 2500 grams/m2/year. The amazon alone accounts for 15-25 per cent of all NPP in terrestrial ecosystems.
PHYSICAL FACTORS affecting amazon rainforest water cycle
GEOGLOGY = Impermeable catchments have minimal water storage capacity resulting in rapid run off. Permeable and porous rock such as lime stone and sandstone store rain water and slow runoff. RELIEF= most of the amazon basin comprises extensive Low lands. In areas of gentle relief water moves across surfaces s or horizontally through the soil to rivers/streams. The west Andes creates steep aments and rapid runoff. TEMPERATURE= high temperature throughout the yea generate high rates of evapotranspiration . convection is strong leading to high atmospheric humidity and development of clouds. This water is cycled continually.
amazon deforestation
However, recently legislations that currently protect 44 per cent of the Amazon are in place to reduce deforestation and restore equilibrium. For example, the Afforestation projects such as Parica project in Rondônia in the western amazon. This sustainable forestry scheme aims to develop 1000km2 commercial timber plantation on government-owned, deforested land. They are determined to re-establish processes like infiltration by planting 20 million fast-growing, tropical hardwood seedling, planted over 4000 small holdings to mature over 25 years. Although the process is a monoculture and cannot replicate the biodiversity of the primary rainforest, it is sustainable. It also reduces run-off and the loss of plant nutrients and carbon from the soil. Also, in Rondônia, the indigenous Suruí people participate in a scheme that aims to protect primary rainforest on tribal lands from further illegal logging, and reforested areas degraded by deforestation in the past 40 years. The Suruí plant seedlings bred in local nurseries in deforested areas around their villages. The native species planted are chosen to provide them with timber for construction, food crops and, through logging a sustainable source of income. With regard to the significance of this human factors are actually the future of the amazon rainforest. the water cycle would not have been damaged if it wasn't for deforestation however human factors like afforestation schemes have proved that change is possible.
Human factors affect the water cycle more significantly in the tropical rainforest than in the arctic tundra- CONCLUSION
In conclusion, I do agree with the statement that human factors affect the water cycle more significantly in the tropical rainforest than in the arctic tundra because the amazon ecosystem relies more on the water cycle as it is much more biodiverse. The water cycle depends more on the climate and vegetation in tropical rainforests therefore humans can have a more significant impact on the cycle. Moreover, the impact in the tropical rainforest is on a much larger and long-term scale than in the Arctic Tundra. however, we still must not disregard the impacts on the water cycle on the Arctic tundra as they are still significant, but the arctic tundra may be able to naturally restore itself to its balance once oil and gas exploitation decreases thus meaning the significance has eased.
WATER CYLE IN THE ARCTIC TUNDRA
In spite of this it could be argued that oil and gas production has impacted the water cycle in Alaska more than in the Amazon rainforest. The north slope of Alaska, between the Brooks Range in the south and the Arctic Ocean in the north, is a vast wilderness of arctic tundra. Oil and gas were discovered here at Prudhoe bay in 1968. From the start the development of the oil and gas industries on the North Slope presented major challenges. Despite all of this and the extreme climate, production went ahead, riven by a high global energy prices and the US government's policy to reduce dependence on oil imports. Oil and gas exploitation on Alaska's North Slope has had significant impacts on the permafrost and on the local water cycle. The melting of the permafrost and snow cover increases run-off and river discharge making flooding more likely. This means that in summer, wetlands, ponds and lakes have become more extensive, increasing evaporation. Strip mining of aggregates (sand and gravel) for construction creates artificial lakes which disrupt drainage networks and also expose the permafrost top further melting. In addition, drainage networks are disputed by road construction and by seismic explosions used to prospect for oil and gas. Moreover, water abstracted from creeks and rivers for industrial use and for the building of ice roads in winter reduce localised run-off. On top of this, the melting of permafrost primarily leads to increased evaporation in the arctic tundra as meltwater is stored on the surface as puddles and small lakes. This will lead to more precipitation as cloud formation is increased, and the annual rainfall total in the arctic tundra will rise to over 200mm, the highest average currently. This will cause imbalance in equilibrium and result in a positive feedback loop that leads to surface storage and evaporation. This seems significant but when compared to the impacts in the amazon it is not as large. Only one process is affected as there is no other large store such as vegetation which is contrasting to the tropical rainforest. And the human factors which affect the water cycle in the arctic tundra are more short term than deforestation in the rainforest which has been going on for a long period of time.
WATER CYCLE IN AMAZON
It could be argued that human factors affecting the water cycle in the Amazon are more significant than the arctic tundra. Deforestation is the main human impact on a tropical rainforest. Deforestation in Amazonia averaged around 17500 km2/year between 1970 and 2013. Since 1970 almost one-fifth of the primary forest has been destroyed or degraded, though in recent years rates of deforestation have slowed. Deforestation has a huge impact on the water cycle and has the potential to change climate at local and regional scales. Converting rainforest to grassland increases run-off by a factor of 27, and half of all the rain falling on the grassland goes directly to rivers. Rainforest trees are a crucial part of the water cycle, extracting moisture form the soil, intercepting rainfall and releasing it to the atmosphere through transpiration as well as stabilising forest albedo and ground temperature which implies how deforestation effects the rainforest in a negative way . This cycle sustains high atmospheric humidity which is responsible for cloud formation and heavy convectional rainfall. Deforestation breaks this cycle and can lead to permanent climate change. This is a short-term impact of disforestation on the water cycle, but it is still significant. However, the impact of deforestation on the water cycles is not just local and short term. Projections of future deforestation in Amazonia predict a 20 per cent decline in regional rainfall as the rainforest dries out a forest trees are gradually replaced by grassland. Nor is it just deforested areas that experience a reduction in rainfall: disruption of the regional water cycle means that forests hundreds of kilometres downwind of degraded sites are affected too furthermore this is a long-term impact of deforestation. Therefore, due to deforestation by human's have impacted the water cycle and so made the climate dries which will also change the water cycle. This human impact can be seen on regional and local scales as well as long term and short term.
What is an open system.
It has inputs and outputs of both energy and matter. E.g. Drainage basin system
What is a closed system?
It has inputs and outputs of energy but no matter eg. water and carbon cycle.
what is an isolated system ?
It has no inputs or outputs and is rare in nature.
What is Negative feedback ?
It's stabilises the system, allowing it to maintain the dynamic equilibrium.
Management strategies can be used to reverse long term changes in the cycles
The key feature of the carbon and water cycles are the atmosphere, biosphere, the rocks and the ocean. Long term changes usually are changes which have been happening since 1960 and the industrial revolution. Climate change is a long-term change which has been impacting the water cycle since the industrial revolution. Global warming has increased evaporation and therefore the amount of water vapour in the atmosphere which has a feedback effect, helping to raise global temperatures. Meanwhile, this can also lead to higher run-off in the water cycle and therefore greater flood risk. Global warming is also accelerating the melting of glacier, ice sheets like Greenland and permafrost in the arctic tundra. However, the impact of global climate change on the carbon cycle is more complex. It depends on not just on rising temperatures but also on geographical differences in rainfall amounts. Higher global temperatures will in general increase rated of decomposition and accelerate transfer of carbon from the biosphere and soil to the atmosphere. In contrast in high latitudes, global warming will allow the boreal forest of Siberia and Canada and Alaska to expand poleward. Carbon in the permafrost in the arctic tundra is melting due to rising temperatures and therefore releasing trapped carbon. Thus, long term climate change will probably see an increase in carbon stored in the atmosphere. Management strategies are designed to protect the global carbon and water cycles as the regulator of the earth's climate include international agreements, afforestation and drainage basin management however it is extremely difficult for these strategies to reverse the long-term changes which have been happening for decades.
What is positive feedback?
The system experiences further change, continues to disrupt the equilibrium.
What are system models?
They show us a concept of geography and show us how components (stores) are linked through flows or transfers. they generally exist within a certain boundary.
What would happen if there was impermeable rock?
This will cause the ground to saturate and increase surface runoff into the channel flow. where as permeable rocks allow for infiltration and percolation to happen
climate change effects the water cycle in the tropical rainforest
climate change can also have a large impact on the water cycle, the temperatures in the amazon are high alleys throughout the year with very small seasonal variations. Thees high average temperatures are a response to intense insolation throughout the year. However, significant cloud cover ensures maximum temperatures do not reach the extremes of the sub-topical desire climates. Seasonal differences in temperatures are small and convectional rain falls all year round, though most areas experience at least one drier period. As temperatures are increasing it effects the precipitation rate and cloud formation. High temperatures throughout the year also generate high rates of evapotranspiration. convection is strong leading to high atmospheric humidity, the development of thunderstorm clouds and intense precipitation. Water is cycled continually between the land surface, forest trees and the atmosphere by evaporation, transpiration and precipitation.
What are the local flows of water?
flows are how water moves from one stored to the other. infiltrations, through flow, percolation, stem flow, base flow channel flow and surface run-off.
How does climate change effect the drainage basin?
in colder climates precipitation falls as snow and there fore is held back until melted. this may reduce channel flow in winter but increase in spring when the snow melts.
What are the local stores of water?
interception, vegetation storage, surface storage, soil moisture and ground water storage.
what are the three types of systems ?
isolated, closed and open
What are the processes in the water cycle?
precipitation, evaporation, transpiration, Cryosphere exchange and runoff
Human factors affect the water cycle more significantly in the tropical rainforest than in the arctic tundra- INTRO
the arctic tundra and the rainforests are two of the most differing ecosystems in the world . The arctic tundra is classified as a cold, icy desert with permafrost which underlies much of the tundra. Climate conditions in the tundra are severe and become more extreme with latitude, an example of a tundra I have studied is Alaska. Whereas tropical rainforest is the opposite; it is dominated by tall, evergreen, hardwood trees. The climate consists of high average annual temperatures between 25 and 30 degrees Celsius with very small seasonal variation in temperature additionally it has a very high annual rainfall (>2000 mm) with no dry season. An example of a tropical rainforest I have studied is the amazon rainforest. Both of these ecosystems rely heavily on the water cycle to develop. The global water cycle consists of three main stores: the atmosphere, oceans and land. The oceans are by far the biggest store and the atmosphere is the smallest. Water moves between these stores by precipitation, evaporation, run-off and groundwater flow. Human factors such as deforestation, climate change and afforestation schemes affect the water cycle in the amazon. Whereas the human factors such as local settlements and oil extraction impact the water cycle in the arctic tundra. I agree with the statement that the water cycle in tropical rainforests are more significantly affected than in the arctic tundra.
How does vegetation affect the drainage basin?
when an area has high coverage of vegetation, the interception and evaporation increases but the surface runoff decreases.