https://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&feed=atom&action=historyThe influence of Climate Change on the water cycle - Revision history2024-03-28T22:45:09ZRevision history for this page on the wikiMediaWiki 1.19.7https://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7902&oldid=prevStefanie Ettling: Stefanie Ettling moved page The influence of climate change on the water cycle to The influence of Climate Change on the water cycle2014-10-14T13:17:55Z<p>Stefanie Ettling moved page <a href="/wiki/The_influence_of_climate_change_on_the_water_cycle" class="mw-redirect" title="The influence of climate change on the water cycle">The influence of climate change on the water cycle</a> to <a href="/wiki/The_influence_of_Climate_Change_on_the_water_cycle" title="The influence of Climate Change on the water cycle">The influence of Climate Change on the water cycle</a></p>
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</tr></table>Stefanie Ettlinghttps://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7893&oldid=prevStefanie Ettling: Stefanie Ettling moved page Influence on the water cycle to The influence of climate change on the water cycle2014-10-14T13:05:16Z<p>Stefanie Ettling moved page <a href="/wiki/Influence_on_the_water_cycle" class="mw-redirect" title="Influence on the water cycle">Influence on the water cycle</a> to <a href="/wiki/The_influence_of_climate_change_on_the_water_cycle" class="mw-redirect" title="The influence of climate change on the water cycle">The influence of climate change on the water cycle</a></p>
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</tr></table>Stefanie Ettlinghttps://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7892&oldid=prevStefanie Ettling at 13:03, 14 October 20142014-10-14T13:03:58Z<p></p>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*Oki, T. and Kanae, S. (2006): Global Hydrological Cycles and World Water Resources. In: ''Science ''313, 1068</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*Oki, T. and Kanae, S. (2006): Global Hydrological Cycles and World Water Resources. In: ''Science ''313, 1068</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*Sherwood, S. and Fu, Q.(2014): A Drier Future? In: ''Science ''343, 737</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*Sherwood, S. and Fu, Q.(2014): A Drier Future? In: ''Science ''343, 737</div></td></tr>
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<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">[[Category:Climate_Change]]</ins></div></td></tr>
</table>Stefanie Ettlinghttps://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7611&oldid=prevFriederike Kraemer at 13:52, 20 May 20142014-05-20T13:52:59Z<p></p>
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<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. [[Portal:<del class="diffchange diffchange-inline">Climate_Change_Background</del>|Climate Change]] and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic [[<del class="diffchange diffchange-inline">Variability_and_extreme_events</del>|variability]], resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. [[Portal:<ins class="diffchange diffchange-inline">Climate Change Background</ins>|Climate Change]] and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic [[<ins class="diffchange diffchange-inline">Variability and extreme events</ins>|variability]], resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>= <span style="<del class="diffchange diffchange-inline">font-size: 22px; </del>line-height: 30.<del class="diffchange diffchange-inline">464000701904297px</del>;">Background</span> =</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>= <span style="line-height: 30.<ins class="diffchange diffchange-inline">46px; font-size: 22px</ins>;">Background</span> =</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The water cycle describes the continuous movement of water in its liquid, solid and vapour forms through the climate system as well as the storage in the reservoirs of ocean, cryosphere, land surface and atmosphere. The main physical processes of the water cycle are evaporation, condensation, precipitation, infiltration, runoff and subsurface flow.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The water cycle describes the continuous movement of water in its liquid, solid and vapour forms through the climate system as well as the storage in the reservoirs of ocean, cryosphere, land surface and atmosphere. The main physical processes of the water cycle are evaporation, condensation, precipitation, infiltration, runoff and subsurface flow.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The movement of water in the climate system is essential to life on land, as much of the water that falls on land as precipitation and supplies the soil moisture and river flow has been evaporated from the ocean and transported to land by the atmosphere. Water that falls as snow in winter can provide soil moisture in springtime and river flow in summer and is essential to both natural and human systems. The movement of fresh water between the atmosphere and the ocean can also influence oceanic salinity, which is an important driver of the density and circulation of the ocean. The latent heat contained in water vapour in the atmosphere is critical to driving the circulation of the atmosphere on scales ranging from individual thunderstorms to the global circulation of the atmosphere (IPCC).</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The movement of water in the climate system is essential to life on land, as much of the water that falls on land as precipitation and supplies the soil moisture and river flow has been evaporated from the ocean and transported to land by the atmosphere. Water that falls as snow in winter can provide soil moisture in springtime and river flow in summer and is essential to both natural and human systems. The movement of fresh water between the atmosphere and the ocean can also influence oceanic salinity, which is an important driver of the density and circulation of the ocean. The latent heat contained in water vapour in the atmosphere is critical to driving the circulation of the atmosphere on scales ranging from individual thunderstorms to the global circulation of the atmosphere (IPCC).</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= Impacts on the Water Cycle =</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= Impacts on the Water Cycle =</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Impacts on agricultural water management - options to scope with water scarcity ==</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Impacts on agricultural water management - options to scope with water scarcity ==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>An intensification of the hydrological cycle will lead to changes in the availability of [[<del class="diffchange diffchange-inline">Impacts_of_climate_change_on_agricultural_water_management</del>|water for agricultural purposes]] and therefore the risk of agricultural drought is likely in presently dry regions. The agricultural sector is the most sensitive to [[<del class="diffchange diffchange-inline">Water_scarcity</del>|water scarcity]], as it accounts for 70 per cent of global freshwater withdrawls, and through intensification and unsustainable practices agriculture is also a cause of water scarcity.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>An intensification of the hydrological cycle will lead to changes in the availability of [[<ins class="diffchange diffchange-inline">Impacts of climate change on agricultural water management</ins>|water for agricultural purposes]] and therefore the risk of agricultural drought is likely in presently dry regions. The agricultural sector is the most sensitive to [[<ins class="diffchange diffchange-inline">Water scarcity</ins>|water scarcity]], as it accounts for 70 per cent of global freshwater withdrawls, and through intensification and unsustainable practices agriculture is also a cause of water scarcity.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>Given the importance of water for agriculture and [[<del class="diffchange diffchange-inline">Definition_and_Dimensions_of_Food_Security</del>|food security]], the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both [[Quantity|quantity]] and [[Quality|quality]] aspects, [[Decision-<del class="diffchange diffchange-inline">making_support</del>|supports decision making]] and is a prerequisite for adaptive management required under conditions of climate change.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>Given the importance of water for agriculture and [[<ins class="diffchange diffchange-inline">Definition and Dimensions of Food Security</ins>|food security]], the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both [[Quantity|quantity]] and [[Quality|quality]] aspects, [[Decision-<ins class="diffchange diffchange-inline">making support</ins>|supports decision making]] and is a prerequisite for adaptive management required under conditions of climate change.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example [[<del class="diffchange diffchange-inline">Water_harvesting</del>|water conservation measures]], access to conventional water resources, [[Reuse|re-use]] of drainage water and wastewater, inter-basin transfers and [[Desalination|desalination]].</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example [[<ins class="diffchange diffchange-inline">Water harvesting</ins>|water conservation measures]], access to conventional water resources, [[Reuse|re-use]] of drainage water and wastewater, inter-basin transfers and [[Desalination|desalination]].</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase [[<del class="diffchange diffchange-inline">Water_use_productivity</del>|water productivity]] and water re-allocation.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase [[<ins class="diffchange diffchange-inline">Water use productivity</ins>|water productivity]] and water re-allocation.</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><br/></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><br/></div></td></tr>
</table>Friederike Kraemerhttps://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7330&oldid=prevChristoph Wagener at 10:14, 11 March 20142014-03-11T10:14:35Z<p></p>
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<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. Climate Change and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic variability, resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. <ins class="diffchange diffchange-inline">[[Portal:Climate_Change_Background|</ins>Climate Change<ins class="diffchange diffchange-inline">]] </ins>and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic <ins class="diffchange diffchange-inline">[[Variability_and_extreme_events|</ins>variability<ins class="diffchange diffchange-inline">]]</ins>, resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= <span style="font-size: 22px; line-height: 30.464000701904297px;">Background</span> =</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= <span style="font-size: 22px; line-height: 30.464000701904297px;">Background</span> =</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Impacts on agricultural water management - options to scope with water scarcity ==</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Impacts on agricultural water management - options to scope with water scarcity ==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>An intensification of the hydrological cycle will lead to changes in the availability of water for agricultural purposes and therefore the risk of agricultural drought is likely in presently dry regions. The agricultural sector is the most sensitive to water scarcity, as it accounts for 70 per cent of global freshwater withdrawls, and through intensification and unsustainable practices agriculture is also a cause of water scarcity.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>An intensification of the hydrological cycle will lead to changes in the availability of <ins class="diffchange diffchange-inline">[[Impacts_of_climate_change_on_agricultural_water_management|</ins>water for agricultural purposes<ins class="diffchange diffchange-inline">]] </ins>and therefore the risk of agricultural drought is likely in presently dry regions. The agricultural sector is the most sensitive to <ins class="diffchange diffchange-inline">[[Water_scarcity|</ins>water scarcity<ins class="diffchange diffchange-inline">]]</ins>, as it accounts for 70 per cent of global freshwater withdrawls, and through intensification and unsustainable practices agriculture is also a cause of water scarcity.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>Given the importance of water for agriculture and food security, the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both quantity and quality aspects, supports decision making and is a prerequisite for adaptive management required under conditions of climate change.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>Given the importance of water for agriculture and <ins class="diffchange diffchange-inline">[[Definition_and_Dimensions_of_Food_Security|</ins>food security<ins class="diffchange diffchange-inline">]]</ins>, the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both <ins class="diffchange diffchange-inline">[[Quantity|</ins>quantity<ins class="diffchange diffchange-inline">]] </ins>and <ins class="diffchange diffchange-inline">[[Quality|</ins>quality<ins class="diffchange diffchange-inline">]] </ins>aspects, <ins class="diffchange diffchange-inline">[[Decision-making_support|</ins>supports decision making<ins class="diffchange diffchange-inline">]] </ins>and is a prerequisite for adaptive management required under conditions of climate change.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example water conservation measures, access to conventional water resources, re-use of drainage water and wastewater, inter-basin transfers and desalination.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example <ins class="diffchange diffchange-inline">[[Water_harvesting|</ins>water conservation measures<ins class="diffchange diffchange-inline">]]</ins>, access to conventional water resources, <ins class="diffchange diffchange-inline">[[Reuse|</ins>re-use<ins class="diffchange diffchange-inline">]] </ins>of drainage water and wastewater, inter-basin transfers and <ins class="diffchange diffchange-inline">[[Desalination|</ins>desalination<ins class="diffchange diffchange-inline">]]</ins>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase water productivity and water re-allocation.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase <ins class="diffchange diffchange-inline">[[Water_use_productivity|</ins>water productivity<ins class="diffchange diffchange-inline">]] </ins>and water re-allocation.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= References and further Information =</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= References and further Information =</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>*Clementz, M.T. and Sewall, J.O. (2011): Latitudinal Gradients in Greenhouse Seawater 18O: Evidence from Eocene Sirenian Tooth Enamel. In: ''Science ''332, 455  </div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>*Clementz, M.T. and Sewall, J.O. (2011): Latitudinal Gradients in Greenhouse Seawater 18O: Evidence from Eocene Sirenian Tooth Enamel. In: ''Science ''332, 455</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*Durack, P.J. et al. (2012): Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000. In: ''Science ''336</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*Durack, P.J. et al. (2012): Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000. In: ''Science ''336</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*FAO (2012): Coping with water scarcity. An action framework for agriculture and food security. Food and Agriculture Organisation of the United Nations, Rome.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>*FAO (2012): Coping with water scarcity. An action framework for agriculture and food security. Food and Agriculture Organisation of the United Nations, Rome.</div></td></tr>
</table>Christoph Wagenerhttps://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7298&oldid=prevChristoph Wagener at 15:22, 6 March 20142014-03-06T15:22:28Z<p></p>
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<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 15:22, 6 March 2014</td>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. Climate Change and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic variability, resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. Climate Change and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic variability, resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><span style="font-size: 22px; line-height: 30.464000701904297px;">Background</span></div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">= </ins><span style="font-size: 22px; line-height: 30.464000701904297px;">Background</span> <ins class="diffchange diffchange-inline">=</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The water cycle describes the continuous movement of water in its liquid, solid and vapour forms through the climate system as well as the storage in the reservoirs of ocean, cryosphere, land surface and atmosphere. The main physical processes of the water cycle are evaporation, condensation, precipitation, infiltration, runoff and subsurface flow.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The water cycle describes the continuous movement of water in its liquid, solid and vapour forms through the climate system as well as the storage in the reservoirs of ocean, cryosphere, land surface and atmosphere. The main physical processes of the water cycle are evaporation, condensation, precipitation, infiltration, runoff and subsurface flow.</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>rainfall events with high runoff amounts are interspersed with longer relatively dry periods</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>rainfall events with high runoff amounts are interspersed with longer relatively dry periods</div></td></tr>
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<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>with increased evapotranspiration, particularly in the subtropics.  </div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>with increased evapotranspiration, particularly in the subtropics.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Specific changes to water resources and the hydrological cycle for example also include:</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Specific changes to water resources and the hydrological cycle for example also include:</div></td></tr>
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<td colspan="2" class="diff-lineno">Line 54:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Given the importance of water for agriculture and food security, the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both quantity and quality aspects, supports decision making and is a prerequisite for adaptive management required under conditions of climate change.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Given the importance of water for agriculture and food security, the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both quantity and quality aspects, supports decision making and is a prerequisite for adaptive management required under conditions of climate change.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example water conservation measures, access to conventional water resources, re-use of drainage water and wastewater, inter-basin transfers and desalination.  </div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example water conservation measures, access to conventional water resources, re-use of drainage water and wastewater, inter-basin transfers and desalination.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase water productivity and water re-allocation.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase water productivity and water re-allocation.</div></td></tr>
<tr><td colspan="2" class="diff-lineno">Line 62:</td>
<td colspan="2" class="diff-lineno">Line 62:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= References and further Information =</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>= References and further Information =</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del class="diffchange diffchange-inline"><br/></del></div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*Clementz, M.T. and Sewall, J.O. (2011): Latitudinal Gradients in Greenhouse Seawater 18O: Evidence from Eocene Sirenian Tooth Enamel. In: ''Science ''332, 455 </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*Durack, P.J. et al. (2012): Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000. In: ''Science ''336</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*FAO (2012): Coping with water scarcity. An action framework for agriculture and food security. Food and Agriculture Organisation of the United Nations, Rome.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*Held, I.M. and Soden, B.J. (2006): Robust Responses of the Hydrological Cycle to Global Warming. In: ''Journal of Climate 19, ''Issue''217''</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*Huntington, T.G. (2006): Evidence for intensification of the global water cycle: Review and synthesis. In: ''Journal of Hydrology'' 319 83–95</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1535 pp</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*Oki, T. and Kanae, S. (2006): Global Hydrological Cycles and World Water Resources. In: ''Science ''313, 1068</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">*Sherwood, S. and Fu, Q.(2014): A Drier Future? In: ''Science ''343, 737</ins></div></td></tr>
</table>Christoph Wagenerhttps://wocatpedia.net/index.php?title=The_influence_of_Climate_Change_on_the_water_cycle&diff=7297&oldid=prevChristoph Wagener: Created page with " There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature ..."2014-03-06T15:21:26Z<p>Created page with " There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature ..."</p>
<p><b>New page</b></p><div><br />
There is a general consensus that global average surface air temperature increased during the 20<sup>th</sup> century and that future warming will happen. Global temperature increase, the key primary outcome of global warming, is expected to reach between 1.8 and 2.8° Celsius by the end of the 21st century relative to the 1980 – 1999 average even in rather moderate scenario. Climate Change and the Water Cycle are directly related. Water is an integral part of the climate system, and changes of the water cycle are expected to happen in nearer future. Climate change will increase hydrologic variability, resulting in extreme weather events such as droughts floods, and major storms. The observed warming over the last decades has led to changing precipitation patterns, to reduced snow cover and widespread melting of ice and to changes in soil moisture and runoff. Precipitation has increased in high northern latitudes and decreased in southern latitudes (IPCC). The probable changes in precipitation and evaporation will translate directly to shifts in the existing pattern of soil moisture deficits, groundwater recharge and runoff. Besides the observed effects of higher temperatures, a change of freshwater availability constitutes an even more important risk to the human society, food security and ecosystems. Although the changes of the water cycle in response to climate change remain difficult to predict, some major points should be addressed.<br />
<br />
<span style="font-size: 22px; line-height: 30.464000701904297px;">Background</span><br />
<br />
The water cycle describes the continuous movement of water in its liquid, solid and vapour forms through the climate system as well as the storage in the reservoirs of ocean, cryosphere, land surface and atmosphere. The main physical processes of the water cycle are evaporation, condensation, precipitation, infiltration, runoff and subsurface flow.<br />
<br />
The movement of water in the climate system is essential to life on land, as much of the water that falls on land as precipitation and supplies the soil moisture and river flow has been evaporated from the ocean and transported to land by the atmosphere. Water that falls as snow in winter can provide soil moisture in springtime and river flow in summer and is essential to both natural and human systems. The movement of fresh water between the atmosphere and the ocean can also influence oceanic salinity, which is an important driver of the density and circulation of the ocean. The latent heat contained in water vapour in the atmosphere is critical to driving the circulation of the atmosphere on scales ranging from individual thunderstorms to the global circulation of the atmosphere (IPCC).<br />
<br />
= Impacts on the Water Cycle =<br />
<br />
The IPCC Report states a “medium confidence” that global change will influence precipitation patterns, but some significant trends can be summarized.<br />
<br />
In the long term, global <u>precipitation</u> will increase due to the higher moisture holding capacity of a warmer atmosphere and higher evaporation rates from warmer water bodies. However, changes in response to the warming over the 21st century will not be uniform. Some regions will experience decreases and some will not experience any changes. There is high confidence that the contrast of annual mean precipitation between dry and wet regions will increase over most of the globe as temperatures increase. High latitudes and moist mid-latitude regions will experience greater amounts of precipitation, whereas many mid-latitude and subtropical arid-and semi-arid regions will experience less precipitation. Importantly, precipitation variability will increase across all regions. Furthermore there will be a shift to more intense <u>extreme events</u>. The intensity of precipitation events and flooding is projected to increase in areas that experience increases in mean precipitation, while there is also a greater risk of droughts in mid-continental areas. Intense and heavy episodic<br />
<br />
rainfall events with high runoff amounts are interspersed with longer relatively dry periods<br />
<br />
with increased evapotranspiration, particularly in the subtropics. <br />
<br />
Specific changes to water resources and the hydrological cycle for example also include:<br />
*Changes in mean surface flows due to natural climate variability at interannual and multidecadal time scales and climate change<br />
*Changes in the seasonality (or timing) of flows, especially in snow melt basins<br />
*Changes in flows from glaciers due to their retreat<br />
*Decreasing snow and permafrost<br />
*Rising sea levels caused by thermal expansion of seawater and melting of continental glaciers<br />
*Changes in soil moisture<br />
<br />
<br/><br />
<br />
Impacts of climate change on annual and decadal weather cycles may also be significant. Examples include the southwest monsoon and the El Niño Southern Oscillation (ENSO) which affects weather in many portions of the globe, including sub-Saharan Africa. Due to the increase in moisture availability, ENSO-related precipitation variability will intensify and remain the dominant mode of interannual variability in tropical pacific.<br />
<br />
There has been scientific discourse about this “intensification” of the water cycle.<br />
<br />
<br/><br />
<br />
== Intensification of the Hydrological Cycle ==<br />
<br />
Climate change adds a number of new aspects to the quantity and availability of water. The mentioned climate changed induced occurrences of extreme events like heavy precipitation, floods and droughts are discussed focusing on the redistribution of precipitation.<br />
<br />
The theoretical basis of this intensification relies on the fact that specific humidity will increase approximately exponentially with temperature.<br />
<br />
According to Durack et al. (2012), this intensification, the greater redistribution of precipitation patterns, is double to the projected response and will be substantial in a future 2° to 3° warmer world. Using the indirect method of ocean salinity patterns expressing the global water cycle, they state an intensification of 16 to 24 % per degree of surface warming. Ocean salinity patterns provide a sensitive and detectable measure of water cycle changes because increasing salinities are found in the evaporation-dominated midlatitudes and decreasing salinities in the rainfall-dominated regions.<br />
<br />
Clementz and Sewall (2011) looked to the Eocene to investigate the relationships between climate and the water cycle. The global physiography was similar to todays, but the climate was different with atmospheric CO2 concentrations about five times higher. They used the phenomena that the stable isotopic composition of water masses is affected by imbalances in evaporation and precipitation and measured the O isotopic composition of carbonate in the tooth enamel of fossil sirenians. This study also offers evidence about the relationship of water cycles and climatic conditions.<br />
<br />
Huntington summarizes numerous results of different publications about time-series analysis of hydroclimatic variables. Precipitation, runoff, tropospheric water vapor, droughts, soil moisture, actual evapotranspiration and growing season length show the trend to increase on regional or global scales. The observed trends are consistent with an intensification of the water cycle, but empirical evidence does not consistently support the idea. He also underlines the large effects human activities can have on the water cycle, for example through air pollution-induced suppression of rainfall or the effects on runoff and infiltration through land-use activities.<br />
<br />
<br/><br />
<br />
== Impacts on agricultural water management - options to scope with water scarcity ==<br />
<br />
An intensification of the hydrological cycle will lead to changes in the availability of water for agricultural purposes and therefore the risk of agricultural drought is likely in presently dry regions. The agricultural sector is the most sensitive to water scarcity, as it accounts for 70 per cent of global freshwater withdrawls, and through intensification and unsustainable practices agriculture is also a cause of water scarcity.<br />
<br />
Given the importance of water for agriculture and food security, the predicted intensification of the water cycle and the probability of improved water scarcity in the future is a challenge that is there to be surmounted. The human society has to be well prepared for such changes and large numbers of people run the risk of living under water stress or seeing their livelihoods devastated by water related hazards. Comprehensive monitoring of water-related variables, in both quantity and quality aspects, supports decision making and is a prerequisite for adaptive management required under conditions of climate change.<br />
<br />
Options to cope with water scarcity in agriculture can be divided between <u>supply enhancement</u> and <u>demand management</u>. Supply enhancement includes for example water conservation measures, access to conventional water resources, re-use of drainage water and wastewater, inter-basin transfers and desalination. <br />
<br />
As the term demand management implies, actions controlling water demand are meant to be implemented. The three options to manage water demand are reduce water losses, increase water productivity and water re-allocation.<br />
<br />
<br/><br />
<br />
= References and further Information =<br />
<br />
<br/></div>Christoph Wagener