<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=ISO-8859-1">
<meta name="Generator" content="Microsoft Word 12 (filtered medium)">
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:14.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.Section1
{page:Section1;}
-->
</style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body bgcolor="#ffffff" text="#000000">
<table class="moz-email-headers-table" border="0" cellpadding="0"
cellspacing="0">
<tbody>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap"><br>
</th>
<td><br>
</td>
<td valign="top"><br>
</td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap"><br>
</th>
<td><br>
</td>
<td valign="top"><br>
</td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap"><br>
</th>
<td><br>
</td>
<td valign="top"><br>
</td>
</tr>
<tr>
<td valign="top"><br>
</td>
<td valign="top"><br>
</td>
<td valign="top"><br>
</td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap"><br>
</th>
<td><br>
</td>
<td valign="top"><br>
</td>
</tr>
</tbody>
</table>
<div class="Section1">
<p class="MsoNormal"><b><span style="font-size: 36pt; color:
blue;">California
Water News</span></b><span style="font-size: 36pt; color:
blue;"><o:p></o:p></span></p>
<p class="MsoNormal"><b><i>A daily compilation for DWR personnel
of significant
news articles and comment</i></b><span style="color: black;"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size: 13.5pt;"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size: 13.5pt;">September
21, 2010</span></b><b><span style="font-size: 13.5pt;
font-family: "Arial","sans-serif";"><o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size: 18pt;">Supply –<o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";">Dust cuts
Colorado River flow, scientists say<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";">L.A.
Times</span></b><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<br>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";">++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";">Dust cuts
Colorado River flow, scientists say<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";">L.A.
Times-9/21/10<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";">By Eryn
Brown<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-family:
"Tahoma","sans-serif";"><o:p> </o:p></span></b></p>
<p class="MsoNormal">The dark dust thrown up by human activity in
the deserts of
the Southwest hastens the melting of Rocky Mountain snow and
ultimately reduces
the amount of water flowing into the upper Colorado River by
about 5%,
scientists reported Monday.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The lost water amounts to more than 250
billion gallons
— enough to supply the Los Angeles region for 18 months, said
study
leader Thomas H. Painter, a snow hydrologist at the Jet
Propulsion Laboratory
in La Cañada Flintridge.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">"That's a lot of water," said Painter, whose
study
was published online by the Proceedings of the National Academy
of Sciences.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Researchers had already shown that dust
emissions in the
Southwest have increased fivefold since the mid-19th century,
when settlers and
their livestock poured across the frontier, breaking up the
fragile crusts atop
desert soils. That extra dust absorbs more sunlight, melting the
snowpack
sooner and shortening the duration of snow cover each year by
three to four
weeks, Painter said.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">To quantify the effect on runoff, Painter and
his colleagues
plugged historical data into a computer model that projected
what annual runoff
would have been from 1916 to 2003 under the cleaner snow
conditions that
existed before 1880.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Accelerated melting due to dust exposes
surface vegetation
earlier in the year, and the growing plants suck water out of
the soil. As a
result, the team calculated, there is 5% less runoff available
to flow into
rivers.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The model did not factor in the likelihood
that a
longer-lasting snowpack also cools the atmosphere, probably
resulting in less
evaporation and more runoff, Painter said. This means the 5%
figure is a
minimum estimate of the amount of Colorado River water that is
lost, he said.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It also suggests that mitigating dust in the
region could
counteract some of the effects of climate change. It would
"allow snowpack
to hang around longer, cool the atmosphere and contribute to
regional
cooling," Painter said.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The study of how color affects the rate at
which snow melts
goes back to a sunny day in the 1720s, when Benjamin Franklin
arrayed pieces of
colored cloth on snow and observed how quickly the patches
beneath them
liquefied.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">"In a few hours, the black, being warmed most
by the
sun, was sunk so low as to be below the stroke of the sun's
rays," he
remarked in a letter to a friend. "The other colors [melted]
less as they
were lighter; and the quite white remained on the surface of the
snow."<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">More recently, scientists have used field
instruments and
satellites to measure dust's effects on snowmelt on small
research plots or
watershed areas of an acre or two, said University of Colorado
snow hydrologist
Mark Williams, who was not part of Painter's team. The new study
marks the
first time that scientists have measured this effect on a vast,
watershed-wide
scale.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Though Williams said he would "quibble" with
some
of the parameters of Painter's computer model — including
estimates of
how much water the early growing plants would draw out of the
system — he
said that improving the model "would affect the magnitude, but
not the
conclusion," of the study.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">"These are intriguing results," he said.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Painter and Williams said that the work had
striking —
and potentially controversial — ramifications for water and
land-use
policy in the Southwest.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The Colorado River and the vast system of
dams and
reservoirs along it supply water to 27 million people in seven
states,
including California, and Mexico. Restoring some of its flows by
cutting dust
emissions could help relieve the longstanding, intractable water
shortages that
have shaped the history of the West.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dust has already decreased since 1934, when
the Taylor
Grazing Act limited the amount of grazing allowed on public
lands. Scientists
have previously analyzed lake deposits and found that dust
production fell 17%
as a result, Painter said.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">But finding the collective will to cut dust
emissions
further would not be easy. Potential measures include banning
the use of
all-terrain vehicles and imposing further restrictions on
grazing.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">"I can't see too many politicians with enough
backbone
to make it work," Williams said.#<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a moz-do-not-send="true"
href="http://www.latimes.com/news/science/la-sci-colorado-river-dust-20100921,0,6434114.story">http://www.latimes.com/news/science/la-sci-colorado-river-dust-20100921,0,6434114.story</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size: 11pt; font-family:
"Tahoma","sans-serif";"><o:p> </o:p></span></b></p>
<br>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";">++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";">DWR’s
California Water News is distributed to California Department
of Water
Resources management and staff, for information purposes, by
the DWR
Public Affairs Office. For reader’s services, including new
subscriptions, temporary cancellations and address changes,
please use the
online page: <a moz-do-not-send="true"
href="http://listhost2.water.ca.gov/mailman/listinfo/water_news"
title="http://listhost2.water.ca.gov/mailman/listinfo/water_news">http://listhost2.water.ca.gov/mailman/listinfo/water_news</a>
. DWR operates and maintains the State Water Project, provides
dam safety and
flood control and inspection services, assists local water
districts in water
management and water conservation planning, and plans for
future statewide
water needs. Inclusion of materials is not to be construed as
an endorsement of
any programs, projects, or viewpoints by the Department or the
State of
California. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt; font-family:
"Calibri","sans-serif";"><o:p> </o:p></span></p>
</div>
</body>
</html>