What is the Weather difference between and climate ? Weather and climate are not independent. Our communities and farms are affected by short- The confusion comes from weather and climate being term weather events. Their long-term sustainability is intimately connected to each other, and this confusion affected by climate and climate variability attributed to is often highlighted in discussions about our changing natural processes and human activities. Figure 1 depicts climate. Weather and climate are not independent. The how weather and climate are intertwined. Over time, the averages of daily weather are used to monitor climate. weather forms the climate and influences the environ- Changes in climate lead to changes in weather patterns ment (soil, hydrology, plants, and animals), and economic including extremes. An easy way to remember the differ- viability of our human systems. ence is that climate is what you expect, like a hot summer, and weather is what you get, like a cool day in August. The sun is the major Extreme weather source of energy events, such as heat for the planet. waves, droughts, The atmosphere tornadoes, torrential moderates the rains, and heavy H2O solar influence snowfall, are a by moderating natural part of the temperature. Earth’s climate. Nonetheless, CH4 extreme weather and climate events have significant CO 2 oxyg effects on our CO e 2 n lives and on the c arbo environment. n H2O c arb o Greenhouse gases, n Carbon dioxide is such as water vapor, constantly being carbon dioxide, exchanged among CO2 methane, and the atmosphere, nitrous oxide, absorb ocean, and land H2O energy and trap it H2O as it is both in the atmosphere. produced and CH4 Activities such as N2O absorbed by many urbanization, energy microorganisms, consumption, land plants, and animals. use change, and agriculture influence the environment. Figure 1. Communities and farms are affected by short-term weather events. Their long-term sustainability is affected by climate (long-term weather variation or expected weather) and climate variability driven by natural and human processes. Weather The concept of climate has broadened and evolved Weather is the behavior of atmosphere at any given in recent decades in response to the increased under- moment. It is what we observe on a daily or weekly basis standing of the underlying processes that determine and includes, but is not limited to, sunshine, rain, cloud climate and its variability. Earth’s climate starts with the cover, wind, hail, snow, sleet, freezing rain, blizzards, ice sun, the sole energy source for our planet. Climate is storms, and thunderstorms. influenced by interactions involving the sun, ocean, atmo- sphere, clouds, ice, land, and living organisms (Figure 1). We generally think about weather and how it Often, this is thought of as the “climate system.” Climate affects our lives and activities. Weather can change varies by region as a result of local differences in these from minute-to-minute, hour-to-hour, day-to-day, and interactions. The Great Plains has a continental climate. season-to-season. This features wide variability from season to season and year to year, with little moderating effect from large water Climate bodies. Climate is the long-term aggregation of weather that occurs in an area and the extent to which those conditions Climate Normals vary over long time intervals. When scientists talk about Meteorologists and climatologists regularly use climate, they are looking at patterns of precipitation, “normal” for placing recent climate conditions into a temperature, humidity, sunshine, wind speed, fog, frost, historical context. Climate “normals” are three-decade and other variables, such as soil temperature and mois- averages of climatological variables, including tempera- ture, that occur over a long period in a particular place. ture (Figures 2 and 3) and precipitation (Figures 4 and 5). Normal Temperatures (1981-2010) for Ottawa, KS Normal rainfall (1981-2010) for ottawa, ks 100 6.00 90 5.00 80 70 4.00 F) ° 60 ) in. 50 3.00 40 Rainfall ( Temperature ( 2.00 30 20 Maximum temperature Minimum temperature 1.00 10 Mean temperature 0 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Date Date Figure 2. Ottawa, Kansas daily temperature normals for the 1981- Figure 4. Ottawa, Kansas rainfall normals by month for the 1981- 2010 period. 2010 period. Normal Temperatures (1981-2010) for Minco, OK Normal rainfall (1981-2010) for minco, ok 100 6.00 90 5.00 80 70 4.00 F) ° 60 ) in. 50 3.00 40 Rainfall ( Temperature ( 2.00 30 20 Maximum temperature Minimum temperature 1.00 10 Mean temperature 0 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Date Date Figure 3. Minco, Oklahoma daily temperature normals for the 1981- Figure 5. Minco, Oklahoma rainfall normals by month for the 1981- 2010 period. 2010 period. A “normal” of a particular variable (e.g., temperature) Key Points is defined as the 30-year average. The current normal • Weather represents the atmospheric events period in the United States is based on 1981 through 2010 data. over a short time period, such as in a minute, an hour, or a day. For example, the January minimum temperature normal for Ottawa, Kansas (19.3 degrees Fahrenheit) • Climate represents aggregate weather is computed by calculating the average minimum conditions over longer time periods, such as daily temperature in January for each year from 1981 decades or centuries. to 2010 and then averaging those values. NOAA’s • Climate “normal” is the official three-decade National Climatic Data Center (NCDC) released the 1981 through 2010 Normals on July 1, 2011. average of weather variables, such as air temperature and precipitation. Because climate normals provide a historical perspec- tive and help us understand the unusualness of current weather, they are commonly seen on local weather news segments for comparisons with the day’s weather condi- tions. Graphing the high, low, and mean temperature for a single year over the normal for that location can help you visualize how well conditions fit into the typical pattern Normal Temperatures vs Daily values for Ottawa, KS (Figures 6 and 7). 120 100 80 F) Glossary ° Climate – The “average weather” or more 60 specifically the statistical aspects of the atmo- sphere-hydrosphere-land surface system that varies Temperature ( 40 over time ranging from months to millions of years. 20 The classical period for averaging climatic variables as defined by the World Meteorological Organization 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec is 30 years. Climate also describes long-term statis- Date tical averages and measures of variability associated Normal maximum Daily high 2013 Normal minimum Daily low 2013 with daily weather. Normal mean Daily mean 2013 Climate change – Any systematic shift in the long-term statistics of weather elements (such Figure 6. Ottawa, Kansas daily temperatures for 2013 compared to as temperature, rainfall, or winds) sustained over 1981-2010 normals. several decades or longer. This can include changes to both averages of these elements as well as Normal Temperatures vs Daily values for minco, ok measures of variability and extremes. These changes 120 can be caused by natural forcing (see definition for 100 forcing(s) below), such as changes in solar emission 80 or slow changes in the Earth’s orbital elements; by F) ° natural internal processes of the climate system, such as glaciations; or by human activities (anthro- 60 pogenic forcing; for further information see Temperature ( 40 references). Climate normal – The latest three-decade aver- 20 ages of climatological variables, including tempera- 0 ture and precipitation. Climate normals are updated Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec every 10 years, when data for the last full decade Date Normal maximum Daily high 2013 have been compiled. Normal minimum Daily low 2013 Normal mean Daily mean 2013 Figure 7. Minco, Oklahoma daily temperatures for 2013 compared to 1981-2010 normals. References Climate variability – The pattern and range Peter Tomlinson, DeAnn Presley, and Chuck Rice, of climate parameters (aggregate weather) for a Greenhouse Gases in Agriculture, MF3119, Kansas State particular place or region over a given time period. University, September 2013 These may include temperature, precipitation, and frequency of extreme events. Forcing – An agent that causes a change in a Resources system, such as a climate system. A volcanic eruption Kansas is an example of a natural forcing that can change ‒ Kansas Weather Data Library (climate.ksu.edu) the composition of the atmosphere. Oklahoma Precipitation – All forms of water particles that ‒ Oklahoma Mesonet (mesonet.org) fall from the atmosphere and reach the ground. ‒ Oklahoma Climatological Survey (climate.ok.gov) These include rain, snow, sleet, and hail. It does not include fog or dew, as those are not falling; nor does Regional it include virga, water droplets or ice that form in ‒ High Plains Regional Climate Center clouds but evaporate before reaching the ground. (hprcc.unl.edu) Weather – The specific conditions of the atmo- ‒ Southern Climate Impacts Planning Program sphere at a particular place and time, measured in (southernclimate.org) terms of variables that include temperature, precipi- National tation, cloudiness, humidity, air pressure, and wind. ‒ National Weather Service (weather.gov) ‒ NOAA Climate Science and Information (climate.gov) ‒ National Climate Data Center (ncdc.noaa.gov) Authors Peter Tomlinson, Assistant Professor, Kansas State University Mary Knapp, Assistant State Climatologist, Kansas State University Albert Sutherland, Assistant Extension Specialist, Oklahoma State University Amber Campbell, Adjunct Assistant Professor and Project Manager, Kansas State University This material is based upon work supported by: U.S.