Confronting climate change head on to improve water management is a cop-out. The best way to manage water better is to manage water better. Pricing water for agriculture could reduce waste dramatically. In Indonesia, a ten per cent reduction in water use for agriculture would be roughly equivalent to present total domestic and industrial water use. Some estimates place water losses and waste in irrigation as high as 50%. Such waste of water has been attributed to high subsidies for water use in agriculture. Where infrastructure for irrigation systems are also subsidized, the effective subsidy for water use probably reaches several hundred per cent. Mismanagement of water caused the degradation of the Aral Sea, not climate change. Geologists in Kansas project by 2065 or so the Ogallala Aquifer will be 70% depleted. Depletion of fossil water is caused also by poor management whether in Kansas or the Sultanate of Oman. The only thing that has saved the Issyk Kul (Kirgyzstan) is its salinity, low as it is. Reducing water use for paddy rice has been shown to save water, increase yields, and reduce methane generation. (I believe the IRRI has confirmed this by experiment.) In Egypt and elsewhere, watter-logging in parts of fields results because fields are not level. Excess water is used because of field configuration. Some countries and regions claim climate change is the cause of water stress for crops and periodic drought. Look more closely at centennial scale data for Australia and California and you will discover long histories of periodic drought. More recently we have learned that severe ENSO events are associated with water stress. Yet these are precisely the regions that export most of their water in the form of crops. (Severe ENSO events are not considered to be related to climate change, though still discussed in the literature.) Finally, the paper by Belda et Al (2014) is probably the best to date in reconstructing the global Koppen-Trewartha climate classification map. The maps show the climate regions of the world (except Antarctica) for two periods, 1901-1931 and 1975-2005, based on a 30 minute grid, average area about 2500 km2, (About 50,000 grid cells cover 135 million km2, the land area of the Earth except Antarctica.) Between the two periods separated by 75 years, 8% of the cells changed climate type. When you plot a scatter diagram of distributions for the two periods, you will find there is little divergence from the straight line passing through the origin and with slope unity. R-squared is 99.5. The paper does not discuss error bars. However the data used has since been revised to remove wet bias, an adjustment that would increase R-squared, indicating even less change in climate-related ecological conditions than these maps show. (Global estimates of precipitation increase during the last 150 years have recently been revised downwards.) In any other field of Earth science, using data with similar precision, we would claim confirmation of the null hypothesis that the two data sets separated by 75 years are not significantly different. So yes, climate has changed a little, but most people worldwide are better off than their parents and grandparents. The people benefiting the most are those on the margins of steppe to desert and those on the margins between ice and tundra where warming and additional rainfall have had the most positive economic effects. Tropical areas show little change. Most studies of water deficit in relation to needs do not take into account the huge expansion in need for water that has been generated by the more than doubling of population since 1950 and the associated land-use changes both urban and rural, including the expansion of land under irrigation. Without urbanization, made possible by plentiful cheap energy, global water needs would be dramatically greater than what they now. We should therefore be cautious in what we aim for in respect to climate and the means to achieve it. To focus on the effects of global warming of a degree Celsius since the depths of the Little Ice Age misses the point entirely. Maps prepared using satellite data to depict the NDVI have shown decades of greening that has been attributed to reduced need of plants for water resulting from reduced evapotranspiration, a physiological response of plants to increased CO2. By all means, let us aim for better water management. But the main challenges are political and financial, specifically over-subsidization of water, which encourages mismanagement, both by bureaucrats supported by development banks and development cooperation agencies, and wasted by water users mainly in irrigation. The adverse consequences are economic and social. Reference:Climate classification revisited from Köppen to Trewartha, Belda, M. et al, Climate Research, 2014http://www.int-res.com/articles/cr_oa/c059p001.pdf NDVIhttp://visibleearth.nasa.gov/view.php?id=1804 http://www.co2science.org/subject/g/summaries/greeningearth.php
Published by Fred Colbourne, Financial Management Specialist - PPP (independent)
Confronting climate change head on to improve water management is a cop-out.
The best way to manage water better is to manage water better.
Pricing water for agriculture could reduce waste dramatically. In Indonesia, a ten per cent reduction in water use for agriculture would be roughly equivalent to present total domestic and industrial water use.
Some estimates place water losses and waste in irrigation as high as 50%. Such waste of water has been attributed to high subsidies for water use in agriculture. Where infrastructure for irrigation systems are also subsidized, the effective subsidy for water use probably reaches several hundred per cent.
Mismanagement of water caused the degradation of the Aral Sea, not climate change.
Geologists in Kansas project by 2065 or so the Ogallala Aquifer will be 70% depleted. Depletion of fossil water is caused also by poor management whether in Kansas or the Sultanate of Oman. The only thing that has saved the Issyk Kul (Kirgyzstan) is its salinity, low as it is.
Reducing water use for paddy rice has been shown to save water, increase yields, and reduce methane generation. (I believe the IRRI has confirmed this by experiment.)
In Egypt and elsewhere, watter-logging in parts of fields results because fields are not level. Excess water is used because of field configuration.
Some countries and regions claim climate change is the cause of water stress for crops and periodic drought. Look more closely at centennial scale data for Australia and California and you will discover long histories of periodic drought. More recently we have learned that severe ENSO events are associated with water stress. Yet these are precisely the regions that export most of their water in the form of crops. (Severe ENSO events are not considered to be related to climate change, though still discussed in the literature.)
Finally, the paper by Belda et Al (2014) is probably the best to date in reconstructing the global Koppen-Trewartha climate classification map. The maps show the climate regions of the world (except Antarctica) for two periods, 1901-1931 and 1975-2005, based on a 30 minute grid, average area about 2500 km2, (About 50,000 grid cells cover 135 million km2, the land area of the Earth except Antarctica.)
Between the two periods separated by 75 years, 8% of the cells changed climate type. When you plot a scatter diagram of distributions for the two periods, you will find there is little divergence from the straight line passing through the origin and with slope unity. R-squared is 99.5.
The paper does not discuss error bars. However the data used has since been revised to remove wet bias, an adjustment that would increase R-squared, indicating even less change in climate-related ecological conditions than these maps show. (Global estimates of precipitation increase during the last 150 years have recently been revised downwards.)
In any other field of Earth science, using data with similar precision, we would claim confirmation of the null hypothesis that the two data sets separated by 75 years are not significantly different.
So yes, climate has changed a little, but most people worldwide are better off than their parents and grandparents. The people benefiting the most are those on the margins of steppe to desert and those on the margins between ice and tundra where warming and additional rainfall have had the most positive economic effects. Tropical areas show little change.
Most studies of water deficit in relation to needs do not take into account the huge expansion in need for water that has been generated by the more than doubling of population since 1950 and the associated land-use changes both urban and rural, including the expansion of land under irrigation.
Without urbanization, made possible by plentiful cheap energy, global water needs would be dramatically greater than what they now. We should therefore be cautious in what we aim for in respect to climate and the means to achieve it.
To focus on the effects of global warming of a degree Celsius since the depths of the Little Ice Age misses the point entirely. Maps prepared using satellite data to depict the NDVI have shown decades of greening that has been attributed to reduced need of plants for water resulting from reduced evapotranspiration, a physiological response of plants to increased CO2.
By all means, let us aim for better water management. But the main challenges are political and financial, specifically over-subsidization of water, which encourages mismanagement, both by bureaucrats supported by development banks and development cooperation agencies, and wasted by water users mainly in irrigation. The adverse consequences are economic and social.
Reference:Climate classification revisited from Köppen to Trewartha, Belda, M. et al, Climate Research, 2014http://www.int-res.com/articles/cr_oa/c059p001.pdf
NDVIhttp://visibleearth.nasa.gov/view.php?id=1804
http://www.co2science.org/subject/g/summaries/greeningearth.php
The best way to manage water better is to manage water better.
Pricing water for agriculture could reduce waste dramatically. In Indonesia, a ten per cent reduction in water use for agriculture would be roughly equivalent to present total domestic and industrial water use.
Some estimates place water losses and waste in irrigation as high as 50%. Such waste of water has been attributed to high subsidies for water use in agriculture. Where infrastructure for irrigation systems are also subsidized, the effective subsidy for water use probably reaches several hundred per cent.
Mismanagement of water caused the degradation of the Aral Sea, not climate change.
Geologists in Kansas project by 2065 or so the Ogallala Aquifer will be 70% depleted. Depletion of fossil water is caused also by poor management whether in Kansas or the Sultanate of Oman. The only thing that has saved the Issyk Kul (Kirgyzstan) is its salinity, low as it is.
Reducing water use for paddy rice has been shown to save water, increase yields, and reduce methane generation. (I believe the IRRI has confirmed this by experiment.)
In Egypt and elsewhere, watter-logging in parts of fields results because fields are not level. Excess water is used because of field configuration.
Some countries and regions claim climate change is the cause of water stress for crops and periodic drought. Look more closely at centennial scale data for Australia and California and you will discover long histories of periodic drought. More recently we have learned that severe ENSO events are associated with water stress. Yet these are precisely the regions that export most of their water in the form of crops. (Severe ENSO events are not considered to be related to climate change, though still discussed in the literature.)
Finally, the paper by Belda et Al (2014) is probably the best to date in reconstructing the global Koppen-Trewartha climate classification map. The maps show the climate regions of the world (except Antarctica) for two periods, 1901-1931 and 1975-2005, based on a 30 minute grid, average area about 2500 km2, (About 50,000 grid cells cover 135 million km2, the land area of the Earth except Antarctica.)
Between the two periods separated by 75 years, 8% of the cells changed climate type. When you plot a scatter diagram of distributions for the two periods, you will find there is little divergence from the straight line passing through the origin and with slope unity. R-squared is 99.5.
The paper does not discuss error bars. However the data used has since been revised to remove wet bias, an adjustment that would increase R-squared, indicating even less change in climate-related ecological conditions than these maps show. (Global estimates of precipitation increase during the last 150 years have recently been revised downwards.)
In any other field of Earth science, using data with similar precision, we would claim confirmation of the null hypothesis that the two data sets separated by 75 years are not significantly different.
So yes, climate has changed a little, but most people worldwide are better off than their parents and grandparents. The people benefiting the most are those on the margins of steppe to desert and those on the margins between ice and tundra where warming and additional rainfall have had the most positive economic effects. Tropical areas show little change.
Most studies of water deficit in relation to needs do not take into account the huge expansion in need for water that has been generated by the more than doubling of population since 1950 and the associated land-use changes both urban and rural, including the expansion of land under irrigation.
Without urbanization, made possible by plentiful cheap energy, global water needs would be dramatically greater than what they now. We should therefore be cautious in what we aim for in respect to climate and the means to achieve it.
To focus on the effects of global warming of a degree Celsius since the depths of the Little Ice Age misses the point entirely. Maps prepared using satellite data to depict the NDVI have shown decades of greening that has been attributed to reduced need of plants for water resulting from reduced evapotranspiration, a physiological response of plants to increased CO2.
By all means, let us aim for better water management. But the main challenges are political and financial, specifically over-subsidization of water, which encourages mismanagement, both by bureaucrats supported by development banks and development cooperation agencies, and wasted by water users mainly in irrigation. The adverse consequences are economic and social.
Reference:Climate classification revisited from Köppen to Trewartha, Belda, M. et al, Climate Research, 2014http://www.int-res.com/articles/cr_oa/c059p001.pdf
NDVIhttp://visibleearth.nasa.gov/view.php?id=1804
http://www.co2science.org/subject/g/summaries/greeningearth.php