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NOAA — Are you dreaming of a white Christmas?

December 12, 2014 Comments off

Are you dreaming of a white Christmas?
Source: NOAA (Climate.gov)

Minnesota. Maine. Upstate New York. The Allegheny Mountains of Pennsylvania and West Virginia. Practically anywhere in Idaho. And of course, the Rockies or the Sierra Nevada Mountains. These are the places where weather history suggests you want to be if you’re looking for the best chance of a white Christmas.

The map at right shows the historic probability of there being at least 1-inch of snow on the ground in the Lower 48 states on December 25 based on the latest (1981-2010) U.S. Climate Normals from NOAA’s National Climatic Data Center. Dark gray shows places where the probability is less than 10 percent, while white shows probabilities greater than 90 percent.

CRS — Major Disaster Declarations for Snow Assistance and Severe Winter Storms: An Overview (December 1, 2014)

December 9, 2014 Comments off

Major Disaster Declarations for Snow Assistance and Severe Winter Storms: An Overview (PDF)
Source: Congressional Research Service (via Federation of American Scientists)

The Federal Emergency Management Agency (FEMA) provides two types of assistance for winter incidents: (1) snow assistance, and (2) assistance for severe winter storms. The assistance is triggered by a presidential disaster declaration. The criteria used by FEMA to determine whether to recommend a declaration depend on the type of winter incident. Snow assistance is based on record, or near record snowfall according to official government reports on snow accumulations. Acceptable government reports are snowfall amounts measured and published by the National Oceanic and Atmospheric Administration’s National Climatic Data Center, or measurements made by observers from the National Weather Service. Determinations for severe winter storms are based on the severity and magnitude of the event and the capabilities of the state and affected local governments to respond to the incident. Both requests for snow assistance and assistance for severe winter storms must also include the estimated cost of federal and nonfederal public assistance associated with the incident. FEMA divides the estimated cost of federal and nonfederal public assistance by the statewide population to give some measure of the per capita impact the incident has had on the state.

Researchers offer new insights into predicting future droughts in California

December 8, 2014 Comments off

Researchers offer new insights into predicting future droughts in California
Source: NOAA

According to a new NOAA-sponsored study, natural oceanic and atmospheric patterns are the primary drivers behind California’s ongoing drought. A high pressure ridge off the West Coast (typical of historic droughts) prevailed for three winters, blocking important wet season storms, with ocean surface temperature patterns making such a ridge much more likely. Typically, the winter season in California provides the state with a majority of its annual snow and rainfall that replenish water supplies for communities and ecosystems.

Further studies on these oceanic conditions and their effect on California’s climate may lead to advances in drought early warning that can help water managers and major industries better prepare for lengthy dry spells in the future.

Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests

December 1, 2014 Comments off

Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests
Source: PLoS ONE

The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

EPA — Climate Change Indicators in the United States — New 2014 Edition

November 27, 2014 Comments off

EPA — Climate Change Indicators in the United States — New 2014 Edition
Source: U.S. Environmental Protection Agency

The Earth’s climate is changing. Temperatures are rising, snow and rainfall patterns are shifting, and more extreme climate events—like heavy rainstorms and record high temperatures—are already taking place. Scientists are highly confident that many of these observed changes can be linked to the climbing levels of carbon dioxide and other greenhouse gases in our atmosphere, which are caused by human activities.

EPA is working with many other organizations to collect and communicate data about climate change. With help from these partners, EPA has compiled the third edition of this report, presenting 30 indicators to help readers understand observed long-term trends related to the causes and effects of climate change. In a manner accessible to all audiences, the report describes the significance of these trends and their possible consequences for people, the environment, and society. Most indicators focus on the United States, but some include global trends to provide context or a basis for comparison, or because they are intrinsically global in nature. All of the indicators presented relate to either the causes or effects of climate change, although some indicators show trends that can be more directly linked to human-induced climate change than others. EPA’s indicators are based on peer-reviewed, publicly-available data from various government agencies, academic institutions, and other organizations. EPA selected these indicators based on the quality of the data and other criteria, using historical records that go back in time as far as possible without sacrificing data quality.

Indicators will be updated periodically on the Web as newer data become available.

Joblessness, Inequality the New Normal as Geopolitical Trends Climb Global Agenda

November 10, 2014 Comments off

Joblessness, Inequality the New Normal as Geopolitical Trends Climb Global Agenda
Source: World Economic Forum

Deepening income inequality and jobless growth head the Top 10 trends for 2015, according to the Outlook on the Global Agenda, which is published today. These long-standing economic challenges are joined in this year’s survey by growing political and environmental concerns.

The trends are based on a survey of almost 1,800 experts from the Forum’s Network of Global Agenda Councils as well as other communities within the World Economic Forum on what they believe will preoccupy leaders over the coming 12-18 months.

The Top 10 Trends for 2015 are:

  1. Deepening income inequality
  2. Persistent jobless growth
  3. Lack of leadership
  4. Rising geostrategic competition
  5. Weakening of representative democracy
  6. Rising pollution in the developing world
  7. Increasing occurrence of severe weather events
  8. Intensifying nationalism
  9. Increasing water stress
  10. Growing importance of health in the economy

The prominence of inequality and unemployment at the top of the list signifies that they are viewed even more severely than in previous years, with stagnating wages contributing to a vicious cycle of entrenched inequality through suppressed growth and employment prospects.

Weather-driven energy intensity increase led to higher energy-related emissions in 2013

October 23, 2014 Comments off

Weather-driven energy intensity increase led to higher energy-related emissions in 2013
Source: Energy Information Administration

U.S. energy-related carbon dioxide (CO2) emissions increased in 2013 by 129 million metric tons (2.5%), the largest increase since 2010 and the fourth-largest increase since 1990. Emissions trends reflect a combination of economic factors (population multiplied by per capita output [GDP/population]), energy intensity (energy use per dollar of GDP), and carbon intensity (carbon emissions per unit of energy consumed).

In the decade prior to 2013, energy intensity decreased on average by 2.0% per year; given that it increased by 0.5% in 2013, this meant there was a 2.5% swing compared to trend. Energy intensity changes can reflect weather variations that directly affect energy use for heating and cooling as well as changes in the composition of economic activity. Heating degree days, a measure of heating requirements, increased about 19% between 2012 and 2013. As compared to the 2003-12 trend, the increase in energy intensity added about 134 million metric tons.

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