Colorado Drought: North and South (Do we have a new normal?) Nolan Doesken Colorado State Climatologist Colorado Climate Center Atmospheric Science Department Colorado State University http://ccc.atmos.colostate.edu Presented to the 2013
Download ReportTranscript Colorado Drought: North and South (Do we have a new normal?) Nolan Doesken Colorado State Climatologist Colorado Climate Center Atmospheric Science Department Colorado State University http://ccc.atmos.colostate.edu Presented to the 2013
Colorado Drought: North and South (Do we have a new normal?) Nolan Doesken Colorado State Climatologist Colorado Climate Center Atmospheric Science Department Colorado State University http://ccc.atmos.colostate.edu Presented to the 2013 Colorado Water Workshop July 17, 2013 Gunnison, Colorado Graphics prepared by Zach Schwalbe Topics we will cover today • Data gratitude • What we know (or think we know) about our Colorado climate • Our current drought – is the worst over? • Where 2012 fit in the historic perspective • Yet another appeal for rain gauges in Colorado First – Let’s think back . . . On this date (July 17) in Gunnison history. . . high low temperature temperature precipitation 1913 74F 40F 0.00” 1963 87F 42F 0.00” 1988 81F 45F 0.04” 2003 87F 48F 0.00” 2012 74F 43F 0.06” 30-yr Avg. 80F 44F 0.05 All-time 89F warmest 52F wettest 0.63” record 64F coolest 31F A moment of gratitude for DATA Thanks to the National Weather Service and their many Cooperators Fort Collins,CO Cooperative Weather Station 1880s to present The National Weather Service still faithfully maintains a “taken for granted” network of very basic weather stations -- the Cooperative Observer Network Photo by Christopher Davey Across the entire nation Providing a valuable historic perspective on our climate Thanks to the USDA Natural Resources Conservation Service Typical NRCS Snotel Site Tracking our snow and its water content!! Snow surveys since the 1930s Credit: NOAA Photo Library April 1 Colorado Statewide Snowpack Thanks to the USGS and the State Engineer’s office series Gunnison River Streamflow Gauge – Here in Gunnison Thanks to the Colorado Climate Center at CSU CSU’s Colorado Agricultural Meteorological Network “CoAgMet” CoAgMet tracks many agsensitive weather variables including evapotranspiration Record Ref ET in 2013 Volunteers at Work – CoCoRaHS (Community Collaborative Rain, Hail and Snow Network) Photos by H. Reges Tracking nationwide precipitation Monday, July 15, 2013 24-hour rainfall And Tracking Colorado precipitation (Yeah!! Finally some big rains!) Please don’t take our hydromet data for granted! We all want it. We all need it. We all use it. But it’s not easy to pay for it So appreciate it and support it What do we know or think we know about our Colorado Climate? Our Climate has a seasonal rhythm Fruita, Colo. Precipitation patterns have strong “seasonality” and geographic diversity Water Year Average Precipitation for Selected Stations Grand Junction Vail Nov Jan Vail Pass Georgetown Denver Burlington 5.0 4.5 Precipitation (inches) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 Oct Dec Feb Mar Apr May Jun Jul Aug Sep oops 2011 Average 2013 2012 2002 Colorado River at COUT Stateline Weather varies from day to day Climate varies from year to year Things are never stationary! Colorado Statewide Mean Annual Temperature (1895-2011) Colorado Statewide Mean Annual Temperatures 1895-20 Where we fit in the national picture Except for our mountains, we’re already very dry most of the time. Large (actually “Huge”) Year-toYear Variations in Precipitation Are we ever “Average”? Probably not. Period of Record Average 1981-2010 Average 2012 Snow is “Way Important” in our climate and hydrology And then there’s drought Drought – an unwelcome but regular visitor Photo by NRCS Drought in SE Colorado 2013 Dang it – we though this was only something from the past Photo by Lyric Lucero Manzanola, CO Severe and widespread drought impacts Colorado on a regular basis So -- Here we go again Recent upward trends in temperatures, especially in spring and summer, may be making matters worse. Comparison of monthly temperature averages 1951-1980 base period versus 1981-2010 Evolution of recent Drought Conditions Leading up to 2012 Drought rolls on Colorado Precipitation in Historic Perspective Water Year 2012 5th driest (Period of Record 1895-2012) Colorado Mean Spring (MAM) Temperatures Spring 2012 was 2nd Warmest (18952012) 49 degrees F, 5.7 degree above the average Colorado Mean Summer (JJA) Temperatures Summer 2012 was the Warmest (1895-2012) 69.7 degrees F, 4.6 degree above the average Average Annual Temperature History for Colorado (NCDC) Calendar Year 2012 2nd Warmest (1895-2012) 48.6 degrees F, 3.6 degrees above average Colorado Winters had been warming, but have leveled off recently, at least for now Several major floods have occurred in Colorado during drought periods e.g. 1935, 1938, 1955, 1965, 1976, 1981, etc So PLEASE be aware! Note – 1997 was NOT a drought year for Colorado The Fort Collins Flood of July 28, 1997 Which “F” word Fire or Flood? Weekly Climate Updates Available Upper Colorado Regional Drought Early Warning Down 16% from last week If weekly drought updates would be useful to you Please give me your contact info today We’ll get you on our regional Drought Monitoring e-mail list You will never again go all week without getting e-mail Please Help Us Monitor Colorado’s Precipitation! Photos by H. Reges How many volunteers do we need? To adequately capture the variations in precipitation • Our goal is at least one per square mile over urban/suburban areas. • One per 36 square miles over rural areas. Join the Team! Or help us find other rain gaugers Community Collaborative Rain, Hail and Snow Network http://www.cocorahs.org Colorado Climate Center Data and Power Point Presentations available for downloading http://ccc.atmos.colostate.edu – Click on “Presentations”