Fęrsluflokkur: Afleišingar

Um yfirvofandi Litla Ķsöld

Nś keppast żmsir viš aš benda į fréttir sem birtast į pressan.is og mbl.is um yfirvofandi litla ķsöld - vegna minni sólvirkni og vegna möguleikans į žvķ aš sś sólvirkni eigi eftir aš minnka enn frekar, jafnvel svo aš lęgšin fari nišur ķ sama far og į sautjįndu öld. Žęr fréttir eru hafšar eftir BBC sem žykir almennt séš frekar įreišanlegur mišill og žvķ ešlilegt aš sumir gapi, enda vita flestir aš hnattręn hlżnun er į fullu gasi og ekkert sem bendir til žess aš hśn sé į undanhaldi - sķšur en svo.

Žaš er einmitt svo aš žegar betur er aš gįš, žį er frétt BBC alls ekki į sama veg og hjį pressan.is eša mbl.is. Vissulega er fréttin um minni sólvirkni, en žaš fylgir sögunni hjį BBC aš žó sólvirknin haldi įfram aš minnka, žį hafi žaš lķtil sem engin įhrif į hina hnattręnu hlżnun - gefum Prófessor Mike Lockwood oršiš:

"If we take all the science that we know relating to how the Sun emits heat and light and how that heat and light powers our climate system, and we look at the climate system globally, the difference that it makes even going back into Maunder Minimum conditions is very small.
"I've done a number of studies that show at the very most it might buy you about five years before you reach a certain global average temperature level. But that's not to say, on a more regional basis there aren't changes to the patterns of our weather that we'll have to get used to."

Vķsindamenn telja žvķ aš žetta geti tafiš hina hnattręnu hlżnun kannski um fimm įr, ž.e. ef įstand sólar fer nišur ķ sama far og į sautjįndu öld. Stašbundiš geti žessar breytingar žó valdiš žvķ aš žaš verši nokkuš kaldara yfir vetrartķmann į įkvešnum svęšum, t.d. ķ noršur Evrópu.

Einhverra hluta vegna sleppa pressan.is og mbl.is aš śtskżra hvaš žetta žżšir fyrir okkur ķ dag - aš žessi afdrifarķka breyting ķ sólinni nśna myndi rétt duga til aš setja hlżnunina ķ pįsu og žessar fréttastofur gefa sér aš möguleg minnkandi sólvirkni hafi sömu įhrif nś og į sautjįndu öld.

En viš skulum lķta ašeins į hvaš er til ķ žvķ aš kuldatķmabil eša kuldaskeiš sé ķ vęndum.

Litla Ķsöldin og nśverandi hlżnun

Sjį nįnar į loftslag.is: Um yfirvofandi Litla Ķsöld


mbl.is Kaldari vešur og sjaldséš noršurljós?
Tilkynna um óvišeigandi tengingu viš frétt

Enn og aftur eru fingraför mannkyns į hnattręnu hlżnunina stašfest

Enn og aftur kemur fram rannsókn sem stašfestir mannleg įhrif į hnattręna hlżnun, ķ žetta skiptiš varšandi hlżnun sjįvar į heimsvķsu. Hér undir mį sjį stutt yfirlit į ensku og tengil į frétt Skeptical Science um mįliš.

 


Gleckler et al Confirm the Human Fingerprint in Global Ocean Warming
(via Skeptical Science)

Posted on 27 June 2012 by dana1981 Although over 90% of overall global warming goes into heating the oceans, it is often overlooked, particularly by those who try to deny that global warming is still happening. Nature Climate Change has a new paper by some big names in the field of oceanography,…

Tengt efni į loftslag.is:

Rangfęrslum haldiš til haga

Mbl.is tekst aš klśšra žżšingu į frétt BBC. Ķ frétt BBC er sagt frį rangfęrslu varšandi brįšnun jökla ķ Himalaya og įrtališ 2035, sem viš į loftslag.is höfum mešal annars sagt frį įšur, sjį tengla hér undir. 

Žaš er ķ raun merkilegt aš eftirfarandi orš į BBC;

The response of Himalayan glaciers to global warming has been a hot topic ever since the 2007 report of the Intergovernmental Panel on Climate Change (IPCC), which contained the erroneous claim that ice from most of the region could disappear by 2035.

séu žżdd į žessa veru į mbl.is:

Rannsóknir sżna aš jöklar ķ Himalaya eru aš minnka og raunar benda rannsóknir til aš žeir kunni aš vera horfnir aš mestu įriš 2035.

Žetta er rangfęrsla sem ekki žarf aš halda į lofti og er dęmi um frekar sljóa fréttamennsku aš gera ekki betri žżšingu en žetta į žessari annars merkilegu frétt af BBC, žar sem eftirfarandi kemur m.a. fram:

...though it is well known from studies in other parts of the world that climate change can cause extra precipitation into cold regions which, if they are cold enough, gets added to the existing mass of ice. 

Hitt er svo annaš mįl aš žaš segir ekki mikiš varšandi hnattręna hlżnun žó sumir jökla Asķu stękki. Žaš žarf t.d. aš taka tillit til afkomu jökla ķ heild, ef žaš į t.d. aš skoša įhrif hnattręnnar hlżnunar, sem einhverjir vilja tengja žessa frétt viš.  

Tengt efni į loftslag.is:


mbl.is Sumir jöklar ķ Asķu aš stękka
Tilkynna um óvišeigandi tengingu viš frétt

Hrašir flutningar, hęrra og lengra

Ķ Science birtist nżlega grein um rannsókn, žar sem sżnt er fram į tengsl milli hinnar hnattręnu hlżnunar og flutning plantna og dżra til hęrri breiddargrįša og upp ķ meiri hęš yfir sjįvarmįl. Aš auki kom ķ ljós aš lķfverur flytjast um set, um tvisvar til žrisvar sinnum hrašar en įšur var tališ.

[...]

Nįnar mį lesa um žetta į loftslag.is, Hrašir flutningar, hęrra og lengra

Tengt efni į loftslag.is


Tröllakrabbinn – įgengur viš Sušurskautslandiš

Lķkt og ķ vķsindaskįldsögu, žį viršist sem žśsundir tröllakrabba séu į leišinni upp landgrunnshlķšar Sušurskautsins. Žeir viršast koma af miklu dżpi, um 6-9 žśsund feta dżpi – sem samsvarar um 1800-2700 m dżpi.

Ķ  milljónir įra hefur lķfrķki landgrunnsins viš Sušurskautiš veriš laust viš rįndżr ķ lķkingu viš tröllakrabbann, aš žvķ aš tališ er – žvķ er lķklegt aš mjśkskelja lķfverur Sušurskautsins, sem žróast hafa fjarri slķkum dżrum, eigi eftir aš fara illa śt śr žessari innrįs.

[...]

Nįnar į loftslag.is, Tröllakrabbinn – įgengur viš Sušurskautslandiš - žar sem einnig mį sjį stutt myndband um efniš.

Tengt efni į loftslag.is

 


Samfélög trjįa į flakki

Nś žegar mikil hlżnun er aš verša į svęšum temprašra skóga Rśsslands, eru samfélög trjįa aš fęrast til noršurs, t.d. hin sķgręnu tré raušgreni og žinur. Į sama tķma žį eru nyrstu samfélögin aš hnigna og sérstaklega einkennistegund landsvęšana ķ noršurhluta Rśsslands, lerki.

Vķsindamenn frį hįskólanum ķ Virginķu unnu aš rannsókninni og komust aš žvķ aš žessi fęrsla muni aukast į nęstu įratugum vegna grundvallarmismunar į lerki og sķgręnum trjįm.

[...]

Nįnar mį lesa um žetta į loftslag.is, Samfélög trjįa į flakki

Tengt efni į loftslag.is

 


Villur og umfjöllun um breytingar hjį IPCC

Ķ tilefni af fréttum um breytingar innan IPCC sem vęntanlega voru óumflżjanlegar og ešlilegar eftir žį gagnrżni (réttmęta jafnt sem óréttmęta) sem duniš hefur yfir nefndina er rétt aš endurbirta eftirfarandi af loftslag.is, žar sem nokkrir vķsindamenn ķ Bandarķkjunum skrifušu opiš bréf um störf IPCC. Okkur žykja umręddar villur hafa fengiš fullmikiš plįss ķ fréttinni į mbl.is og žaš hefši aš ósekju mįtt ręša um breytingarnar sjįlfar meira. Viš munum vęntanlega skoša skżrslu og nišurstöšur fagrįšs vķsindamannanna meira į nęstunni, en žangaš til smį upprifjun ķ formi eftirfarandi:

Nokkrir vķsindamenn ķ Bandarķkjunum hafa tekiš sig saman og skrifaš opiš bréf um störf IPCC og villur žęr sem fundist hafa ķ fjóršu matsskżrslu IPCC um loftslagsmįl frį 2007.

Nś žegar hafa um 250 vķsindamenn skrifaš undir žetta bréf og enn er veriš aš safna undirskriftum. Til aš sjį allan lista undirskrifenda, vinsamlega skošiš žessa sķšu. Föstudaginn 12. mars var bréfiš afhent stjórnvöldum. Stór hluti žeirra sem skrifa undir bréfiš eru vķsindamenn sem rannsaka loftslagsbreytingar og vinna viš leišandi stofnanir og hįskóla ķ Bandarķkjunum. Žar er bęši aš finna höfunda efnis ķ skżrlsur IPCC og žį sem ekki hafa tekiš žįtt ķ žeirri vinnu. Til višbótar mį nefna undirskrifendur sem stunda rannsóknir į tengdum efnum, mį žar m.a. nefna į vķsindamenn į sviši ešlis-, lķf- og félagsfręša.

Viš hér į Loftslag.is, ętlum aš birta bréfiš eins og žaš kemur frį höfundum, į ensku. Gjöriš svo vel.

***********************************************

Many in the popular press and other media, as well as some in the halls of Congress, are seizing on a few errors that have been found in the Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) in an attempt to discredit the entire report.  None of the handful of mis-statements (out of hundreds and hundreds of unchallenged statements) remotely undermines the conclusion that “warming of the climate system is unequivocal” and that most of the observed increase in global average temperatures since the mid-twentieth century is very likely due to observed increase in anthropogenic greenhouse gas concentrations. Despite its excellent performance for accurately reporting the state-of-the-science, we certainly acknowledge that the IPCC should become more forthcoming in openly acknowledging errors in a timely fashion, and continuing to improve its assessment procedures to further lower the already very low rate of error.

It is our intention in offering this open letter to bring the focus back to credible science, rather than invented hyperbole, so that it can bear on the policy debate in the United States and throughout the world.  We first discuss some of the key messages from climate science and then elaborate on IPCC procedures, with particular attention to the quality-control mechanisms of the IPCC.  Finally we offer some suggestions about what might be done next to improve IPCC practices and restore full trust in climate science.

The Climate Challenge
Our understanding of human contributions to climate change and the associated urgency for humans to respond has improved dramatically over the past two decades.  Many of the major components of the climate system are now well understood, though there are still sources of significant uncertainty (like the processes that produce the observed rapid ice-sheet melting and/or collapse in the polar regions).  It is now well established, for example, that atmospheric concentrations of greenhouse gases from human sources have increased rapidly since the Industrial Revolution.  Increasing concentrations of greenhouse gases in the atmosphere reduce the heat going out of the climate system, i.e., the radiation balance of the Earth – and so first principles of physics tell us to expect, with a very high likelihood, that higher temperatures should have been observed.

Indeed, measurements of global average temperatures show an increase of about 0.6 degrees C over the twentieth century and about 0.8 degrees C warming since mid-19th century.  The pattern of increase has not been smooth or monotonic.  There have been several 10- to 15-year periods of stable or declining temperatures over the past 150 years, but 14 of the warmest 15 years on record have been experienced between 1995 and 2009.  Since 1970, observational evidence from all continents and most oceans shows that many natural systems are already being affected by these temperature increases.

Because the long-term warming trends are highly significant relative to our estimates of the magnitude of natural variability, the current decadal period of stable global mean temperature does nothing to alter a fundamental conclusion from the AR4: warming has unequivocally been observed and documented.  Moreover, well-understood lags in the responsiveness of the climate system to disturbances like greenhouse gas increases mean that the current temperature plateau will very likely not persist much longer. Global climate model projections show that present-day greenhouse gas concentrations have already committed the planet to about 0.5 degree C in warming over this century.

Increasing emissions of carbon dioxide from the consumption of coal, oil and natural gas as well as deforestation have been the major drivers of this observed warming.  While we cannot predict the details of our climate future with a high degree of certainty, the majority of studies from a large number of research groups in the US and elsewhere project that unabated emissions could produce between 1 and 6 degrees C more warming through the year 2100.

Other research has identified multiple reasons to be concerned about climate change; these apply to the United States as well as globally.  They include (1) risks to unique and threatened systems (including human communities), (2) risks from extreme events (like coastal storms, floods, droughts, heat waves, and wildfires), (3) economic damages (driven by, for example, pest infestations or inequities in the capacity to adapt), (4) risks from large-scale abrupt climate change (e.g., ice-sheet collapse, ocean circulation slowing, sharply increased methane emissions from permafrost) or abrupt impacts of more predictable climate change (generated by thresholds in the coping capacities of natural and human systems to climate variability), and (5) risks to national security (driven largely by extreme events across the world interacting with already-stressed situations).

These sources of risk and the potential for triggering temperature-driven impacts at lower thresholds, as well as the explicit recognition in the AR4 that risk is the product of likelihood and consequence, led the nations of the world to take note of the Copenhagen Accord last December.  The Accord highlights 2 degrees C in warming as a target that might reduce the chance of “dangerous anthropogenic interference with the climate system” to more manageable levels.  Research has shown that increasing the likelihood of achieving this goal over the next century is economically and technically feasible with emission reduction measures and changes in consumption patterns; but it will not be easy without major national and international actions to deviate substantially from the status quo.

The IPCC and the Fourth Assessment Report 
The World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) established the IPCC in 1988 to provide policy makers regularly with balanced assessments of the state of knowledge on climate change.  In so doing, they created an open intergovernmental organization in which scientists, policy analysts, engineers, and resource managers from all over the world were asked to collaborate.  At present, more than 150 countries including the United States participate in the IPCC.  IPCC publishes an assessment report approximately every six years.  The most recent Fourth Assessment, approved by member countries and released in 2007, contained three volumes: The Physical Science Basis (Working Group I); Impacts, Adaptation and Vulnerability (Working Group II) and Mitigation of Climate Change (Working Group III) and a Synthesis Report.  More than 44 writing teams and 450 lead authors contributed to the Fourth Assessment – authors who have been selected on the basis of their expertise in consultation with all member countries and who were assisted by another 800 scientists and analysts who served as contributing authors on specific topics.  Authors donated their time gratis, and the entire process was supported by four Technical Support Units (TSUs) that employ 5 to 10 people each.

Errors in the Fourth Assessment Report

It was hard not to notice the extraordinary commotion that erupted around errors that were eventually found in the AR4.  The wrong year for the projected disappearance of the Himalayan glaciers and the wrong percentage of ‘land below sea level’ in the Netherlands are examples of errors that need to be acknowledged frankly and rectified promptly.  In a few other cases, like the discussion of the correlations between crop yields, climate change, and climate variability in North Africa, caveats that were carefully crafted within the chapters were not included when language was shortened for the Synthesis Report. While striving to simplify technical details and summarize major points, some important qualifications were left behind. These errors of omission in the summary process should also be recognized and corrected. Other claims, like the one reported at the end of February suggesting that the AR4 did not mention the millions of more people who will see increases in water availability that were reported in the cited literature along with the millions of more people who will be at risk of water shortage, are simply not true.  In any case, it is essential to emphasize that none of these interventions alter the key finding from the AR4 that human beings are very likely changing the climate, with far-reaching impacts in the long run.

The heated debates that have emerged around these instances have even led some to question the quality and integrity of the IPCC.  Recent events have made it clear that the quality control procedures of the IPCC are not watertight, but claims of widespread and deliberate manipulation of scientific data and fundamental conclusions in the AR4 are not supported by the facts.  We also strongly contest the impression that the main conclusions of the report are based on dubious sources. The reference list of the AR4 contains about 18,000 citations, the vast majority of which were published in peer-reviewed scientific journals. The IPCC also has transparent procedures for using published but not peer-reviewed sources in their reports.  These procedures were not properly followed in the isolated Himalaya case, but that statement was never elevated into the Summary for Policymakers of either Working Group II or the Synthesis Report – documents that were approved unanimously and word for word by all member nations.

Nonetheless, failsafe compliance with these procedures requires extra attention in the writing of the next round of assessments.  We propose implementing a topic-based cross-chapter review process by which experts in an impact area of climate change, such as changes in water resources, scrutinize the assessment of related vulnerability, risk analyses, and adaptation strategies that work downstream from such changes.  Here we mean, to continue the example, assessments of possible increases in flooding damage in river basins and the potential for wetlands to provide buffers in the sectoral and regional chapters. This would be most productively implemented just before the first-order draft, so that chapter authors can be alerted to potential problems before the major review step.

Quality Control within the IPCC and US Review
The impression that the IPCC does not have a proper quality-control procedure is deeply mistaken. The procedure for compiling reports and assuring its quality control is governed by well-documented principles that are reviewed regularly and amended as appropriate.  Even now, every step in the preparation of every chapter can be traced on a website: First Order Drafts (with comments by many scientists as well as author responses to those comments),Second Order Drafts in which those comments are incorporated (and comments by experts and country representatives on revised versions as well as another round of author responses), and so on, up through the final, plenary-approved versions.

To be clear, 2,500 reviewers together provided about 90,000 comments on the 44 chapters for the AR4.  Each comment is documented on a website that also describes how and why the comment was or was not incorporated in the next revision.  Review editors for each chapter worked with the authors to guarantee that each comment was treated properly and honestly in the revision; in fact, no chapter can ever move forward for publication without the approval of its set of two or three review editors.

The US Government opened its reviews of the draft IPCC report to any US expert who wanted to review it. In order to protect against having this preliminary pre-reviewed draft leaked before its ultimate approval by the IPCC Plenary, the US Government asked all potential reviewers to agree not to disclose the contents of the draft.  For each report, the US Government assembled its own independent panel of government experts to vet the comments before submission to the IPCC. Anything with scientific merit was forwarded.  There were multiple rounds for each of the Working Group reports and the Synthesis Report, and opportunities for US experts to review the drafts were posted as Federal Register notices.

IPCC principles also govern how authors treat published but non-peer reviewed sources. These procedures acknowledge that peer-reviewed scientific journals contain little information about on-the-ground implementation of adaptation or mitigation – matters such as the emission reduction potential in a given industrial sector or country, for example, or catalogues of the specific vulnerabilities and adaptation strategies of sectors and regions with regard to climate change.  This information is frequently only available in reports from research institutes, reports of workshops and conferences, or in publications from industries or other non-governmental organizations.  This is the so-called gray literature. The IPCC procedure prescribes that authors are obliged to assess critically any graysource that they wish to include. The quality and validity of a finding from a non-peer reviewed source needs to be verified before its finding may be included in a chapter text.  Each source needs to be completely traceable; and in cases where gray sources are used, a copy must be deposited at the IPCC Secretariat to guarantee that it is available upon request for third parties.

We conclude that the IPCC procedures are transparent and thorough, even though they are not infallible.  Nonetheless, we are confident that no single scholar or small group of scholars can manipulate the process to include or to exclude a specific line of research; authors of that research can (and are fully encouraged to) participate in the review process.  Moreover, the work of every scientist, regardless of whether it supports or rejects the premise of human-induced climate change, is subject to inclusion in the reports.  The work is included or rejected for consideration based on its scientific merit.

It is important to note that we are not addressing here the criteria and procedures by which the IPCC selects chairs and authors. These are handled exclusively by the IPCC and its members according to terms of reference that were initially defined in the authorizing language of 1988.  That is to say, governments or their appointees frame and implement these policies; and they create, approve and staff Technical Support Units for each working group. We do not make suggestions on these topics since they lie beyond our purview.

What comes next? 
We expect that the robust findings of the AR4 will be continue to be supported by new information gleaned from literature published since 2006 — i.e., that the climate change issue is serious and real.  Given these findings, we believe that the climate change issue deserves the urgent and non-partisan consideration of the country’s legislative and administrative leaders.  We feel strongly that exaggerated focus on a few errors from 2007 cannot be allowed to detract from open and honest deliberations about how to respond to climate risk by reducing emissions and promoting adaptation at home and abroad.

As the process of producing the IPCC Fifth Assessment Report (AR5) begins, the IPCC should become more responsive in acknowledging errors rapidly and openly as they become known. To this end, we urge the IPCC to put an erratum on its website that rectifies all errors that have been discovered in the text after publication.  In doing so, a clear distinction needs to be made between errors and progressing knowledge.  IPCC assessments are detailed snapshots of the state of scientific knowledge at a given time, while knowledge evolves continuously through ongoing research and experience; it is the errors in the assessments that need immediate attention.  In contrast, progressing knowledge is published in new scientific journal articles and reports; this information should be used as a basis for the AR5, but it cannot be listed as errata for the AR4 because it was not available when that assessment was conducted.  The website should, as well, respond rapidly and openly when reports of errors in past assessments are themselves in error.  We cannot let misperceptions fester anymore than errors go uncorrected.

Climate research and the IPCC reports on the state of knowledge provide a scientific foundation for climate policy making, whose agenda is defined by the governments of the IPCC and not the lead authors per se.  The quality of and the balance in the knowledge delivered by any assessment is certainly essential, as is clear and explicit communication of associated uncertainties.  Given the recent political and media commotion surrounding a few clear errors, it is now equally essential that we find ways to restore full trust in the integrity of the overwhelming majority of the climate change research and policy communities.  To that end, we are pleased that an independent critical evaluation of IPCC procedures will be conducted; we hope that the process will solicit participation by the National Academies of the member nations.

The significance of IPCC errors has been greatly exaggerated by many sensationalist accounts, but that is no reason to avoid implementing procedures to make the assessment process even better. The public has a right to know the risks of climate change as scientists currently understand them. We are dedicated to working with our colleagues and government in furthering that task.

March 10, 2010

Signed:

Gary W. Yohe                          Wesleyan University and Yale School of Forestry and Environmental Studies
gyohe@wesleyan.edu

Stephen H. Schneider               Stanford University
shs@stanford.edu

Cynthia Rosenzweig                 NASA Goddard Institute for Space Studies and Columbia University
crosenzweig@giss.nasa.gov

William E. Easterling               Pennsylvania State University
billeasterling@psu.edu

For a full list of signers please visit this page. 

Tengt efni į loftslag.is:

 


mbl.is Loftslagsnefndin verši stokkuš upp
Tilkynna um óvišeigandi tengingu viš frétt

Sjaldgęfur atburšur

Ķ fréttum vķša um heim komast menn ekki hjį žvķ aš - ķ minnsta lagi - velta žvķ upp hvort hitabylgjan ķ Moskvu sé aš einhverju leiti tengd hlżnun Jaršar.

Loftslagsvķsindamenn eru almennt séš frekar varkįrir ķ yfirlżsingum sķnum, žó fjölmišlar eigi žaš til aš blįsa slķkt upp. Žvķ heyrir mašur oft hjį žeim, aš ekki sé hęgt aš tengja einstaka atburši sem žessa viš hnattręna hlżnun, žótt keyrslur loftslagslķkana hafi einmitt bent į aš slķkir atburšir verši sterkari viš aukiš hnattręnt hitastig. Tölfręšilega hefur reynst erfitt aš henda reišur į žaš hvort hér sé um aš ręša beina afleišingu hnattręnnar hlżnunar - til žess er nįttśrulegur breytileiki of mikill.

Einn tölfręšingur skošaši hitabylgjuna ķ Moskvu, ž.e. hitastig ķ jślķ undanfarin 60 įr eša svo og fékk žessa mynd (sjį Red hot):

dailyhi

Žaš mį ljóst vera aš jślķ 2010 var töluvert heitari en önnur įr į tķmabilinu. Reyndar kom ķ ljós viš žessa tilraun aš hitastig fyrir daglegan hita ķ jślķ 2010 er um 3,6 stašalfrįvik frį mešaltalinu. Fyrir normaldreifš gildi, žį eru lķkurnar į öfgunum ķ Moskvu um 0,0003 - eša um 1 į móti 3000.

Žvķ mį įlykta sem svo aš hér sé mögulega kominn atburšur ķ safniš sem tölfręšilega mį įlykta aš sé beintengdur hnattręnni hlżnun. Žaš mį žó bśast viš žvķ aš loftslagsvķsindamenn og tölfręšingar eigi eftir aš rżna betur ķ gögn sumarsins žegar lķšur nęr vetri, en margt bendir til žess aš hlżnun Jaršar af völdum gróšurhśsalofttegunda, lķtil virkni sólar (og žar meš breytingar ķ vindakerfum) og ENSO Kyrrahafssveiflan hafi allt įtt sinn žįtt ķ žessum vešuröfgum.

Lķklegt mį telja aš vešuröfgar žessa įrs séu eitthvaš sem bśast mį viš aš aukist į nęstu įratugum og öldum (sjį tengla hér fyrir nešan).


mbl.is Hitinn lagši marga aš velli
Tilkynna um óvišeigandi tengingu viš frétt

Lax og silungur viš loftslagsbreytingar

Į loftslag.is skrifušum viš fyrir stuttu frétt žar sem fariš var yfir rannsókn į įhrifum loftslagsbreytinga į laxa og silung, sjį Lax og silingur viš loftslagsbreytingar.

salmon_trout-300x207Lax og silung hefur į undanförnum įratugum fękkaš – og į sumum svęšum töluvert.

Mengun, rżrnun bśsvęša og ofveiši hafa hingaš til veriš taldir helstu sökudólgarnir, en nżjar vķsbendingar benda til žess aš loftslagsbreytingar geti veriš helsti žįtturinn og aš žęr ógni bįšum tegundunum.

Vķsindamennirnir rönnsökušu stofn ungra laxa og silungs ķ įnni Wye ķ Wales, sem er ein af bestu stangveišiįm Bretlandseyja. Žeir fundu śt aš į milli įranna 1985 og 2004, žį fękkaši lax um 50% og silung um 67% – žrįtt fyrir aš įin sjįlf yrši hreinni į žeim tķma.

Haršast uršu fiskarnir śti eftir heit og žur sumur, lķkt og įrin 1990, 2000 og 2003. Nišurstašan bendir til žess aš heitara vatn og lęgri vatnsstaša hafi hvaš mest įhrif į bįšar tegundirnar. Žar sem kalt vatn er kjörsvęši laxa og silungs, žį gęti įframhaldandi hlżnun skapaš enn meiri vanda fyrir žessar tegundir.

Vķsindamennirnir notušu gögn um stofnstęršir fiskanna, sem breska Umhverfisstofununin (British Environment Agency) hafši safnaš į yfir 50 stöšum ķ įnni Wye. Hitastig vatnsins jókst į žessu tķmabili um 0,5-0,7°C yfir sumartķman og 0,7-1,0°C yfir vetrartķman – en hitinn um vetrartķman įsamt minna rennsli ķ įnni hafši mest įhrif. Vitaš er aš vatnshiti hefur įhrif į vöxt og hversu viškvęmur fiskurinn er gagnvart sjśkdómum – en minna rennsli ķ įm hindrar aš hann komist į kaldari bśsvęši.

Samanburšur į laxi og silung eykur gildi žessarar rannsóknar, žar sem silungur – ólķkt laxinum – dvelst ekki ķ sjó. Žvķ eru žaš eingöngu ašstęšur ķ įnni sem hafa įhrif į hann.

Heimildir og ķtarefni

Greinin sjįlf birtist ķ Global Change Biology og er eftir Clews o.fl. 2010:  Juvenile salmonid populations in a temperate river system track synoptic trends in climate

Unniš upp śr frétt af Science Daily: Climate Threatens Trout and Salmon

Tengdar fęrslur į loftslag.is


mbl.is Laxar drepast vegna sśrefnisskorts
Tilkynna um óvišeigandi tengingu viš frétt

Žess vegna hękka gróšurhśsalofttegundir hitastig

Ķ myndbandi, sem hęgt er aš sjį į Loftslag.is, frį ChangingClimates er į einfaldan hįtt fariš yfir žaš hvers vegna gróšurhśsalofttegundir hafa įhrif į hitastig. Reynt er aš lżsa ešli gróšurhśsalofttegunda į leikręnan hįtt, žaš mį spyrja sjįlfan sig hvernig žaš tekst til. Efnislega er innihaldiš žó fróšlegt hverjum žeim sem langar aš kynna sér ešli gróšurhśsalofttegunda į einfaldan hįtt. Eftirfarandi lżsing er viš myndbandiš į YouTube:

Scott Denning, viš Loftslagsvķsindadeild Rķkishįskólans ķ Colorado, śtskżrir į einfaldan hįtt ešli og eiginleika sameinda gróšurhśsalofttegundanna og hvernig žęr fanga hita ķ andrśmsloftinu.

Myndbandiš er hęgt aš sjį į loftslag.is:

Tengt efni af Loftslag.is:


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