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Amazon carbon balance is found to be sensitive to drought

Submitted by: Geoff Zeiss - Published At: 2014-02-27 01:05 - (74 Reads)
Forestry and Agriculture
The Amazon watershed stores a vast amount of carbon. Over the past two decades it has experienced increasingly higher temperatures and more frequent floods and droughts. This article reports annual carbon balances across the Amazon watershed, based on atmospheric carbon dioxide and carbon monoxide measurements for 2010 and 2011. Fortuitously 2010 was an extraordinarily dry year and 2011 was exceptionally wet in the Amazon. It was found that the carbon flux between the non-burned forest and the atmosphere was carbon neutral during the dry year. During the wet year, vegetation sequestered net 0.25 ± 0.14 petagrams of carbon per year (Pg C /yr). Nature,506,76–80 (06 February 2014) doi:10.1038/nature12957(external link)

IPCC AR5 : New Evidence about Climate Change in Earth's Oceans

Submitted by: Rick Higgins - Published At: 2014-02-10 17:48 - (139 Reads)
Marine and Oceans
The Fifth Assessment Report (AR5) of the IPCC states there is strong evidence that four global measures of ocean change have increased since the 1950s: the inventory of anthropogenic carbon dioxide, global mean sea level, upper ocean heat content, and the salinity contrast between regions of high and low sea surface salinity.
About 93% of the excess heat energy stored by the earth over the last 50 years is found in the ocean and changes in ocean heat content dominate changes in the global energy inventory. The report states that global mean sea level (GMSL) rose by 0.19 (0.17 to 0.21) m over the period 1901 to 2010. The rate of sea level rise since the mid-19th century has been larger than the mean rate during the previous two millennia (high confidence). The report concludes with high confidence that the observed patterns of change in the subsurface ocean are consistent with changes in the surface ocean in response to climate change and natural variability and with known physical and biogeochemical processes in the ocean.
IPCC AR5 Chapter 3: Observations: Ocean(external link)

IPCC 5th ASSESSMENT Report : New Evidence about Climate Change in Earth's Atmosphere and Surface

Submitted by: Wendy Aritenang - Published At: 2014-01-23 17:36 - (453 Reads)
Climate
The International Panel on Climate Change (IPCC)'s Fifth Assessment Report (AR5) presents new evidence of climate change based on observations of the climate system, paleoclimate archives, and theoretical studies of climate processes. The global combined land and ocean temperature data (GMST) shows an increase of about 0.89°C (0.69°C–1.08°C) over the period 1901–2012 and about 0.72°C (0.49°C–0.89°C) over the period 1951–2012. Land-surface air temperature and global average sea surface temperatures have increased since the beginning of the 20th century. All ten of the warmest years have occurred since 1997, and 2010 and 2005 were the warmest years. Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850 . In the Northern Hemisphere, 1983–2012 was the warmest 30-year period of the last 1400 years. The report also states that since the 1950s many of the observed changes are unprecedented over decades and in some cases up to millennia. Source ; IPCC AR5 Chapter 2(external link)

IPCC AR5: Earth's energy budget

Submitted by: Geoff Zeiss - Published At: 2013-12-29 12:43 - (130 Reads)
Climate
The energy budget is a conceptual framework for understanding the energy fluxes that are responsible for heating and cooling the Earth. The primary goal of the energy budget is to estimate the net energy imbalance between the solar radiation absorbed by the Earth and the thermal radiation lost by the Earth to outer space because this is responsible for long term heating or cooling trends. This has been difficult to estimate reliably because the imbalance is a small difference on the order of one watt per square meter between large numbers on the order of hundreds of watts per square meter.

Observation of Pacific Ocean heat content over the past 10,000 years

Submitted by: Geoff Zeiss - Published At: 2013-12-28 13:39 - (114 Reads)
Marine and Oceans
It has been argued that the total heat stored in the ocean is a more reliable measure of how Earth’s energy budget responds to radiative changes than are surface temperatures. In this article the authors compiled high-resolution proxy records for ocean temperature and heat content (OHC) from sediment cores from the Makassar Strait and Flores Sea in Indonesia to extend observations of the Pacific OHC 10,000 years beyond the modern instrumental record. Assuming the record near Indonesia is representative of the entire Pacific, their results suggests that Pacific OHC was substantially higher during most of the past 10,000 years than in the past decade (2000 to 2010), except during the Little Ice Age. They also find that the rate of change of Pacific OHC between 1955 and 2010 is the highest in the past 10,000 years. The authors suggest that small changes in high-latitude climate due to radiative forcing are efficiently transferred to the ocean’s interior. Over a long time, the ocean’s interior builds up large heat anomalies that affect the global climate. Science 1 November 2013: Vol. 342 no. 6158 pp. 617-621 DOI: 10.1126/science.1240837 (external link)