Tag Archives: NOAA

If all the ice on Earth melted, would your house be underwater?

Peter Lobner, updated 26 September 2023

Thanks to Lyncean member Mike Spaeth for sending me the article “What would the Earth look like if all the ice melted. The answer is terrifying,” which discusses the worst-case scenario of sea level rise after all the ice and snow currently locked away in glaciers, ice sheets and snowpacks has melted.

The bottom line is a sea level rise of 216 feet (65.8 m).

The article includes a link to a short, dramatic 2015 animated video by the same title, posted by Insider Science, which shows the global effects a 216 ft sea level rise.  You can watch this video on YouTube here: How Earth Would Look If All The Ice Melted

So, what about your neighborhood? You can explore a topographical map of the San Diego area here: https://en-us.topographic-map.com/map-n9tp/San-Diego/. Zoom in to determine the land elevations in specific neighborhoods and find the locations of the 216 ft elevation contour lines.

In the above map, everything in blue would be underwater after a 216 ft sea level rise, including all of Coronado, the Silver Strand, the downtown areas of San Diego, National City and Chula Vista, Lindberg Airport, Pacific Beach, Mission Valley and parts of Point Loma. Ironically, the submarine base near the tip of Point Loma would be underwater.

After you’ve found your house and the houses of families and friends in San Diego, you can expand your topographical search of the whole world.  All it takes is a bit of scrolling & zooming.  Some countries would be completely underwater.

Thanks to Steve Masten for sending me the link to the Sea Level Rise Viewer developed by the National Oceanographic and Atmospheric Administration (NOAA).  With this visualization tool, you can see the gradual effects of sea level rise in coastal USA, up to a maximum rise of 10 feet (3 meters).  Below are example results for San Diego, CA.  

Current San Diego

5 foot (1.5 meter) sea level rise 

Note the modest impacts in low-lying areas, particularly in South Bay.

10 foot (3 meter) sea level rise

There are significant flooded areas along the eastern bayfront from downtown San Diego to National City and Chula Vista. The San Diego Airport and Loma Portal are flooded. Coronado becomes two islands and the Silver Strand is underwater, opening the South Bay to the ocean.  Point Loma has become an island, and the strand of Mission Beach is underwater, opening Mission Bay to the ocean.

Here’s a closer look at the area around San Diego Bay after a 10 foot sea level rise.

For more information

NOAA’s Monthly Climate Summaries are Worth Your Attention

Peter Lobner

The National Oceanic and Atmospheric Administration’s (NOAA’s) National Centers for Environmental Information (NCEI) are responsible for “preserving, monitoring, assessing, and providing public access to the Nation’s treasure of climate and historical weather data and information.”  The main NOAA / NCEI website is here:

https://www.ncdc.noaa.gov

The “State of the Climate” is a collection of monthly summaries recapping climate-related occurrences on both a global and national scale.  Your starting point for accessing this collection is here:

https://www.ncdc.noaa.gov/sotc/

The following monthly summaries are available.

I’d like to direct your attention to two particularly impressive monthly summaries:

  • Global Summary Information, which provides a comprehensive top-level view, including the Sea Ice Index
  • Global Climate Report, which provides more information on temperature and precipitation, but excludes the Sea Ice Index information

Here are some of the graphics from the Global Climate Report for June 2019.

Source: NOAA NCEI
Source: NOAA NCEI

NOAA offered the following synopsis of the global climate for June 2019.

  • The month of June was characterized by warmer-than-average temperatures across much of the world. The most notable warm June 2019 temperature departures from average were observed across central and eastern Europe, northern Russia, northeastern Canada, and southern parts of South America.
  • Averaged as a whole, the June 2019 global land and ocean temperature departure from average was the highest for June since global records began in 1880.
  • Nine of the 10 warmest Junes have occurred since 2010.

For more details, see the online June 2019 Global Climate Reportat the following link:

https://www.ncdc.noaa.gov/sotc/global/201906

A complementary NOAA climate data resource is the National Snow & Ice Data Center’s (NSIDC’s) Sea Ice Index, which provides monthly and daily quick looks at Arctic-wide and Antarctic-wide changes in sea ice. It is a source for consistently processed ice extent and concentration images and data values since 1979. Maps show sea ice extent with an outline of the 30-year (1981-2010) median extent for the corresponding month or day. Other maps show sea ice concentration and anomalies and trends in concentration.  In addition, there are several tools you can use on this website to animate a series of monthly images or to compare anomalies or trends.  You’ll find the Sea Ice Index here:

https://nsidc.org/data/seaice_index/

The Arctic sea ice extent for June 2019 and the latest daily results for 23 July 2019 are shown in the following graphics, which show the rapid shrinkage of the ice pack during the Arctic summer.  NOAA reported that the June 2019 Arctic sea ice extent was 10.5% below the 30-year (1981 – 2010) average.  This is the second smallest June Arctic sea ice extent since satellite records began in 1979.

Source:  NOAA NSIDC
Source:  NOAA NSIDC

The monthly Antarctic results for June 2019 and the latest daily results for 23 July 2019 are shown in the following graphics, which show the growth of the Antarctic ice pack during the southern winter season. NOAA reported that the June 2019 Antarctic sea ice extent was 8.5% below the 30-year (1981 – 2010) average.  This is the smallest June Antarctic sea ice extent on record.

Source:  NOAA NSIDC
Source:  NOAA NSIDC

I hope you enjoy exploring NOAA’s “State of the Climate” collection of monthly summaries.

Severe Space Weather Events Will Challenge Critical Infrastructure Systems on Earth

Peter Lobner

What is space weather?

Space weather is determined largely by the variable effects of the Sun on the Earth’s magnetosphere. The basic geometry of this relationship is shown in the following diagram, with the solar wind always impinging on the Earth’s magnetic field and transferring energy into the magnetosphere.  Normally, the solar wind does not change rapidly, and Earth’s space weather is relatively benign. However, sudden disturbances on the Sun produce solar flares and coronal holes that can cause significant, rapid variations in Earth’s space weather.

auroradiagramSource: http://scijinks.jpl.nasa.gov/aurora/

A solar storm, or geomagnetic storm, typically is associated with a large-scale magnetic eruption on the Sun’s surface that initiates a solar flare and an associated coronal mass ejection (CME). A CME is a giant cloud of electrified gas (solar plasma.) that is cast outward from the Sun and may intersect Earth’s orbit. The solar flare also releases a burst of radiation in the form of solar X-rays and protons.

The solar X-rays travel at the speed of light, arriving at Earth’s orbit in 8 minutes and 20 seconds. Solar protons travel at up to 1/3 the speed of light and take about 30 minutes to reach Earth’s orbit. NOAA reports that CMEs typically travel at a speed of about 300 kilometers per second, but can be as slow as 100 kilometers per second. The CMEs typically take 3 to 5 days to reach the Earth and can take as long as 24 to 36 hours to pass over the Earth, once the leading edge has arrived.

If the Earth is in the path, the X-rays will impinge on the Sun side of the Earth, while charged particles will travel along magnetic field lines and enter Earth’s atmosphere near the north and south poles. The passing CME will transfer energy into the magnetosphere.

Solar storms also may be the result of high-speed solar wind streams (HSS) that emanate from solar coronal holes (an area of the Sun’s corona with a weak magnetic field) with speeds up to 3,000 kilometers per second. The HSS overtakes the slower solar wind, creating turbulent regions (co-rotating interaction regions, CIR) that can reach the Earth’s orbit in as short as 18 hours. A CIR can deposit as much energy into Earth’s magnetosphere as a CME, but over a longer period of time, up to several days.

Solar storms can have significant effects on critical infrastructure systems on Earth, including airborne and space borne systems. The following diagram highlights some of these vulnerabilities.

Canada Geomagnetic-Storms-effects-space-weather-technologyEffects of Space Weather on Modern Technology. Source: SpaceWeather.gc.ca

Characterizing space weather

The U.S. National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center (SWPC) uses the following three scales to characterize space weather:

  • Geomagnetic storms (G): intensity measured by the “planetary geomagnetic disturbance index”, Kp, also known as the Geomagnetic Storm or G-Scale
  • Solar radiation storms (S): intensity measured by the flux level of ≥ 10 MeV solar protons at GEOS (Geostationary Operational Environmental Satellite) satellites, which are in synchronous orbit around the Earth.
  • Radio blackouts (R): intensity measured by flux level of solar X-rays at GEOS satellites.

Another metric of space weather is the Disturbance Storm Time (Dst) index, which is a measure of the strength of a ring current around Earth caused by solar protons and electrons. A negative Dst value means that Earth’s magnetic field is weakened, which is the case during solar storms.

A single solar disturbance (a CME or a CIR) will affect all of the NOAA scales and Dst to some degree.

As shown in the following NOAA table (click on table to enlarge), the G-scale describes the infrastructure effects that can be experienced for five levels of geomagnetic storm severity. At the higher levels of the scale, significant infrastructure outages and damage are possible.

NOAA geomag storm scale

There are similar tables for Solar Radiation Storms and Radio Blackouts on the NOAA SWPC website at the following link:

http://www.swpc.noaa.gov/noaa-scales-explanation

Another source for space weather information is the spaceweather.com website, which contains some information not found on the NOAA SWPC website. For example, this website includes a report of radiation levels in the atmosphere at aviation altitudes and higher in the stratosphere. In the following chart, “dose rates are expressed as multiples of sea level. For instance, we see that boarding a plane that flies at 25,000 feet exposes passengers to dose rates ~10x higher than sea level. At 40,000 feet, the multiplier is closer to 50x.”

 spaceweather rad levelsSource: spaceweather.com

You’ll also find a report of recent and upcoming near-Earth asteroids on the spaceweather.com website. This definitely broadens the meaning of “space weather.” As you can seen the in the following table, no close encounters are predicted over the next two months.

spaceweather NEOs

In summary, the effects of a solar storm may include:

  • Interference with or damage to spacecraft electronics: induced currents and/or energetic particles may have temporary or permanent effects on satellite systems
  • Navigation satellite (GPS, GLONASS and Galileo) UHF / SHF signal scintillation (interference)
  • Increased drag on low Earth orbiting satellites: During storms, currents and energetic particles in the ionosphere add energy in the form of heat that can increase the density of the upper atmosphere, causing extra drag on satellites in low-earth orbit
  • High-frequency (HF) radio communications and low-frequency (LF) radio navigation system interference or signal blackout
  • Geomagnetically induced currents (GICs) in long conductors can trip protective devices and may damage associated hardware and control equipment in electric power transmission and distribution systems, pipelines, and other cable systems on land or undersea.
  • Higher radiation levels experienced by crew & passengers flying at high latitudes in high-altitude aircraft or in spacecraft.

For additional information, you can download the document, “Space Weather – Effects on Technology,” from the Space Weather Canada website at the following link:

http://ftp.maps.canada.ca/pub/nrcan_rncan/publications/ess_sst/292/292124/gid_292124.pdf

Historical major solar storms

The largest recorded geomagnetic storm, known as the Carrington Event or the Solar Storm of 1859, occurred on 1 – 2 September 1859. Effects included:

  • Induced currents in long telegraph wires, interrupting service worldwide, with a few reports of shocks to operators and fires.
  • Aurorea seen as far south as Hawaii, Mexico, Caribbean and Italy.

This event is named after Richard Carrington, the solar astronomer who witnessed the event through his private observatory telescope and sketched the Sun’s sunspots during the event. In 1859, no electric power transmission and distribution system, pipeline, or cable system infrastructure existed, so it’s a bit difficult to appreciate the impact that a Carrington-class event would have on our modern technological infrastructure.

A large geomagnetic storm in March 1989 has been attributed as the cause of the rapid collapse of the Hydro-Quebec power grid as induced voltages caused protective relays to trip, resulting in a cascading failure of the power grid. This event left six million people without electricity for nine hours.

A large solar storm on 23 July 2012, believed to be similar in magnitude to the Carrington Event, was detected by the STEREO-A (Solar TErrestrial RElations Observatory) spacecraft, but the storm passed Earth’s orbit without striking the Earth. STEREO-A and its companion, STEREO-B, are in heliocentric orbits at approximately the same distance from the Sun as Earth, but displaced ahead and behind the Earth to provide a stereoscopic view of the Sun.

You’ll find a historical timeline of solar storms, from the 28 August 1859 Carrington Event to the 29 October 2003 Halloween Storm on the Space Weather website at the following link:

http://www.solarstorms.org/SRefStorms.html

Risk from future solar storms

A 2013 risk assessment by the insurance firm Lloyd’s and consultant engineering firm Atmospheric and Environmental Research (AER) examined the impact of solar storms on North America’s electric grid.

electrical-power-transmission-lines-united-states-useiaU.S. electric power transmission grid. Source: EIA

Here is a summary of the key findings of this risk assessment:

  • A Carrington-level extreme geomagnetic storm is almost inevitable in the future. Historical auroral records suggest a return period of 50 years for Quebec-level (1989) storms and 150 years for very extreme storms, such as the Carrington Event (1859).
  • The risk of intense geomagnetic storms is elevated near the peak of the each 11-year solar cycle, which peaked in 2015.
  • As North American electric infrastructure ages and we become more dependent on electricity, the risk of a catastrophic outage increases with each peak of the solar cycle.
  • Weighted by population, the highest risk of storm-induced power outages in the U.S. is along the Atlantic corridor between Washington D.C. and New York City.
  • The total U.S. population at risk of extended power outage from a Carrington-level storm is between 20-40 million, with durations from 16 days to 1-2 years.
  • Storms weaker than Carrington-level could result in a small number of damaged transformers, but the potential damage in densely populated regions along the Atlantic coast is significant.
  • A severe space weather event that causes major disruption of the electricity network in the U.S. could have major implications for the insurance industry.

The Lloyds report identifies the following relative risk factors for electric power transmission and distribution systems:

  • Magnetic latitude: Higher north and south “corrected” magnetic latitudes are more strongly affected (“corrected” because the magnetic North and South poles are not at the geographic poles). The effects of a major storm can extend to mid-latitudes.
  • Ground conductivity (down to a depth of several hundred meters): Geomagnetic storm effects on grounded infrastructure depend on local ground conductivity, which varies significantly around the U.S.
  • Coast effect: Grounded systems along the coast are affected by currents induced in highly-conductive seawater.
  • Line length and rating: Induced current increases with line length and the kV rating (size) of the line.
  • Transformer design: Lloyds noted that extra-high voltage (EHV) transformers (> 500 kV) used in electrical transmission systems are single-phase transformers. As a class, these are more vulnerable to internal heating than three-phase transformers for the same level of geomagnetically induced current.

Combining these risk factors on a county-by-county basis produced the following relative risk map for the northeast U.S., from New York City to Maine. The relative risk scale covers a range of 1000. The Lloyd’s report states, “This means that for some counties, the chance of an average transformer experiencing a damaging geomagnetically induced current is more than 1000 times that risk in the lowest risk county.”

Lloyds relative risk Relative risk of power outage from geomagnetic storm. Source: Lloyd’s

You can download the complete Lloyd risk assessment at the following link:

https://www.lloyds.com/news-and-insight/risk-insight/library/natural-environment/solar-storm

In May 2013, the United States Federal Energy Regulatory Commission issued a directive to the North American Electric Reliability Corporation (NERC) to develop reliability standards to address the impact of geomagnetic disturbances on the U.S. electrical transmission system. One part of that effort is to accurately characterize geomagnetic induction hazards in the U.S. The most recent results were reported in the 19 September 2016, a paper by J. Love et al., “Geoelectric hazard maps for the continental United States.” In this report the authors characterize geography and surface impedance of many sites in the U.S. and explain how these characteristics contribute to regional differences in geoelectric risk. Key findings are:

“As a result of the combination of geographic differences in geomagnetic activity and Earth surface impedance, once-per-century geoelectric amplitudes span more than 2 orders of magnitude (factor of 100) and are an intricate function of location.”

“Within regions of the United States where a magnetotelluric survey was completed, Minnesota (MN) and Wisconsin (WI) have some of the highest geoelectric hazards, while Florida (FL) has some of the lowest.”

“Across the northern Midwest …..once-per-century geoelectric amplitudes exceed the 2 V/km that Boteler ……has inferred was responsible for bringing down the Hydro-Québec electric-power grid in Canada in March 1989.”

The following maps from this paper show maximum once-per-century geoelectric exceedances at EarthScope and U.S. Geological Survey magnetotelluric survey sites for geomagnetic induction (a) north-south and (b) east-west. In these maps, you can the areas of the upper Midwest that have the highest risk.

JLove Sep2016_grl54980-fig-0004

The complete paper is available online at the following link:

http://onlinelibrary.wiley.com/doi/10.1002/2016GL070469/full

Is the U.S. prepared for a severe solar storm?

The quick answer, “No.” The possibility of a long-duration, continental-scale electric power outage exists. Think about all of the systems and services that are dependent on electric power in your home and your community, including communications, water supply, fuel supply, transportation, navigation, food and commodity distribution, healthcare, schools, industry, and public safety / emergency response. Then extrapolate that statewide and nationwide.

In October 2015, the National Science and Technology Council issued the, “National Space Weather Action Plan,” with the following stated goals:

  • Establish benchmarks for space-weather events: induced geo-electric fields), ionizing radiation, ionospheric disturbances, solar radio bursts, and upper atmospheric expansion
  • Enhance response and recovery capabilities, including preparation of an “All-Hazards Power Outage Response and Recovery Plan.
  • Improve protection and mitigation efforts
  • Improve assessment, modeling, and prediction of impacts on critical infrastructure
  • Improve space weather services through advancing understanding and forecasting
  • Increase international cooperation, including policy-level acknowledgement that space weather is a global challenge

The Action Plan concludes:

“The activities outlined in this Action Plan represent a merging of national and homeland security concerns with scientific interests. This effort is only the first step. The Federal Government alone cannot effectively prepare the Nation for space weather; significant effort must go into engaging the broader community. Space weather poses a significant and complex risk to critical technology and infrastructure, and has the potential to cause substantial economic harm. This Action Plan provides a road map for a collaborative and Federally-coordinated approach to developing effective policies, practices, and procedures for decreasing the Nation’s vulnerabilities.”

You can download the Action Plan at the following link:

https://www.whitehouse.gov/sites/default/files/microsites/ostp/final_nationalspaceweatheractionplan_20151028.pdf

To supplement this Action Plan, on 13 October 2016, the President issued an Executive Order entitled, “Coordinating Efforts to Prepare the Nation for Space Weather Events,” which you can read at the following link:

https://www.whitehouse.gov/the-press-office/2016/10/13/executive-order-coordinating-efforts-prepare-nation-space-weather-events

Implementation of this Executive Order includes the following provision (Section 5):

Within 120 days of the date of this order, the Secretary of Energy, in consultation with the Secretary of Homeland Security, shall develop a plan to test and evaluate available devices that mitigate the effects of geomagnetic disturbances on the electrical power grid through the development of a pilot program that deploys such devices, in situ, in the electrical power grid. After the development of the plan, the Secretary shall implement the plan in collaboration with industry.”

So, steps are being taken to better understand the potential scope of the space weather problems and to initiate long-term efforts to mitigate their effects. Developing a robust national mitigation capability for severe space weather events will take several decades. In the meantime, the nation and the whole world remain very vulnerable to sever space weather.

Today’s space weather forecast

Based on the Electric Power Community Dashboard from NOAA’s Space Weather Prediction Center, it looks like we have mild space weather on 31 December 2016. All three key indices are green: R (radio blackouts), S (solar radiation storms), and G (geomagnetic storms). That’s be a good way to start the New Year.

NOAA space weather 31Dec2016

See your NOAA space weather forecast at:

http://www.swpc.noaa.gov/communities/electric-power-community-dashboard

Natural Resources Canada also forecasts mild space weather for the far north.

Canada space weather 31Dec2016You can see the Canadian space weather forecast at the following link:

http://www.spaceweather.gc.ca/index-en.php

4 January 2017 Update: G1 Geomagnetic Storm Approaching Earth

On 2 January, 2017, NOAA’s Space Weather Prediction Center reported that NASA’s STEREO-A spacecraft encountered a 700 kilometer per second HSS that will be pointed at Earth in a couple of days.

“A G1 (Minor) geomagnetic storm watch is in effect for 4 and 5 January, 2017. A recurrent, polar connected, negative polarity coronal hole high-speed stream (CH HSS) is anticipated to rotate into an Earth-influential position by 4 January. Elevated solar wind speeds and a disturbed interplanetary magnetic field (IMF) are forecast due to the CH HSS. These conditions are likely to produce isolated periods of G1 storming beginning late on 4 January and continuing into 5 January. Continue to check our SWPC website for updated information and forecasts.”

The coronal hole is visible as the darker regions in the following image from NASA’s Solar Dynamics Observatory (SDO) satellite, which is in a geosynchronous orbit around Earth.

NOAA SWPC 4Jan2017Source: NOAA SWPC

SDO has been observing the Sun since 2010 with a set of three instruments:

  • Helioseismic and Magnetic Imager (HMI)
  • Extreme Ultraviolet Variability Experiment (EVE)
  • Atmospheric Imaging Assembly (AIA)

The above image of the coronal hole was made by SDO’s AIA. Another view, from the spaceweather.com website, provides a clearer depiction of the size and shape of the coronal hole creating the current G1 storm.

spaceweather coronal holeSource: spaceweather.com

You’ll find more information on the SDO satellite and mission on the NASA website at the following link:

https://sdo.gsfc.nasa.gov/mission/spacecraft.php

Is it Possible to Attribute Specific Extreme Weather Events to Global Climate Change?

Peter Lobner

On 7 September 2016, the National Oceanic and Atmospheric Administration (NOAA) reported that climate change increased the chance of record rains in Louisiana by at least 40%. This finding was based on a rapid assessment conducted by NOAA and partners after unusually severe and prolonged rains affected a broad area of Louisiana in August 2016. You can read this NOAA news release at the following link:

http://www.noaa.gov/media-release/climate-change-increased-chances-of-record-rains-in-louisiana-by-at-least-40-percent

NOAA reported that models indicated the following:

  • The return period for extreme rain events of the magnitude of the mid-August 2016 downpour in Louisiana has decreased from an average of 50 years to 30 years.
  • A typical 30-year event in 1900 would have had 10% less rain than a similar event today; for example, 23 inches instead of 25 inches.

NOAA notes that “return intervals” are statistical averages over long periods of time, which means that it’s possible to have more than one “30-year event” in a 30-year period.

NOAA Lousiana Aug2016 extreme rain graphSource: NOAA

In their news release NOAA included the following aerial photos of Denham Springs, Louisiana. The photo on the left was at the height of the flooding on August 15, 2016. The photo on the right was taken three days later when floodwaters had receded.

NOAA Lousiana Aug2016 extreme rain photosSource: NOAA / National Geodetic Survey

World Weather Attribution (WWA) is an international effort that is, “designed to sharpen and accelerate the scientific community’s ability to analyze and communicate the possible influence of climate change on extreme-weather events such as storms, floods, heat waves and droughts”. Their website is at the following link:

https://wwa.climatecentral.org

WWA attempts to address the question: “Did climate change have anything to do with this?” but on their website, WWA cautions:

“Scientists are now able to answer this for many types of extremes. But the answer may vary depending on how the question is framed……..it is important for every extreme event attribution study to clearly define the event and state the framing of the attribution question.”

To get a feeling for how they applied this principal, you can read the WWA report, “Louisiana Downpours, August 2016,” at the following link:

https://wwa.climatecentral.org/analyses/louisiana-downpours-august-2016/

I find this report quite helpful in putting the Louisiana extreme precipitation event in perspective. I object to the reference to “human-caused climate change,” in the report because the findings should apply regardless of the source of the observed change in climate between 1900 and 2016.

On the WWA website, you can easily navigate to several other very interesting analyses of extreme weather events, and much more.

The National Academies Press (NAP) recently published the following two reports on extreme weather attribution, both of which are worth your attention.

The first NAP report, “Attribution of Extreme Weather Events in the Context of Climate Change,” applies to the type of rapid assessment performed by NOAA after the August 2016 extreme precipitation event in Louisiana. The basic premise of this report is as follows:

“The media, the public, and decision makers increasingly ask for results from event attribution studies during or directly following an extreme event. To meet this need, some groups are developing rapid and/or operational event attribution systems to provide attribution assessments on faster timescales than the typical research mode timescale, which can often take years.”

NAP Attribution of Severe Weather Events  Source: NAP

If you have established a free NAP account, you can download a pdf copy of this report for free at the following link:

http://www.nap.edu/catalog/21852/attribution-of-extreme-weather-events-in-the-context-of-climate-change

The second NAP report, “Frontiers of Decadal Climate Variability,” addresses a longer-term climate issue. This report documents the results of a September 2015 workshop convened by the National Academies of Sciences, Engineering, and Medicine to examine variability in Earth’s climate on decadal timescales, which they define as 10 to 30 years.

NAP Decadal Climate Variation   Source: NAP

This report puts the importance of understanding decadal climate variability in the following context:

“Many factors contribute to variability in Earth’s climate on a range of timescales, from seasons to decades. Natural climate variability arises from two different sources: (1) internal variability from interactions among components of the climate system, for example, between the ocean and the atmosphere, and (2) natural external forcing (functions), such as variations in the amount of radiation from the Sun. External forcing (functions) on the climate system also arise from some human activities, such as the emission of greenhouse gases (GHGs) and aerosols. The climate that we experience is a combination of all of these factors.

Understanding climate variability on the decadal timescale is important to decision-making. Planners and policy makers want information about decadal variability in order to make decisions in a range of sectors, including for infrastructure, water resources, agriculture, and energy.”

While decadal climate variability is quite different than specific extreme weather events, the decadal variability establishes the underlying climate patterns on which extreme weather events may occur.

You can download a pdf copy of this report for free at the following link:

http://www.nap.edu/catalog/23552/frontiers-in-decadal-climate-variability-proceedings-of-a-workshop

I think it’s fair to say that, in the future, we will be seeing an increasing number of “quick response” attributions of extreme weather events to climate change. Each day in the financial section of the newspaper (Yes, I still get a printed copy of the daily newspaper!), there is an attribution from some source about why the stock market did what it did the previous day. Some days these financial attributions seem to make sense, but other days they’re very much like reading a fortune cookie or horoscope, offering little more than generic platitudes.

Hopefully there will be real science behind attributions of extreme weather events to climate change and the attributors will heed WWA’s caution:

“…it is important for every extreme event attribution study to clearly define the event and state the framing of the attribution question.”