Right on Cue: FOX News on Amazongate

18 Responses to “Right on Cue: FOX News on Amazongate”

1. 

   Layman Lurker Reply January 29, 2010 at 9:28 am

   There is no definitive science linking AGW with ENSO frequency/magnitude. IPCC reports do not suggest this. The Trenberth abstract you cited only speculates at the possible links:

   “Both the recent trend for more ENSO events since 1976 and the prolonged 1990–1995 ENSO event are unexpected given the previous record, with a probability of occurrence about once in 2,000 years. This opens up the possibility that the ENSO changes may be partly caused by the observed increases in greenhouse gases.”

   • 

     willard Reply January 29, 2010 at 12:18 pm

     “Definitive science” : an intriguing concept.

2. 

   Layman Lurker Reply January 29, 2010 at 10:37 am

   Here is an abstract from a recent paper identifying and working with the models which reproduce realistic ENSO variability.

   http://ams.allenpress.com/perlserv/?doi=10.1175%2F2009JCLI3185.1&request=get-abstract

   From the abstract:

   “These models exhibit realistic patterns, magnitude, and spatial extent of El Niño–induced drought patterns in the twentieth century, and the teleconnections are not projected to change in the twenty-first century, although a possible slight reduction in the spatial extent of droughts is indicated over the tropics as a whole. All model groups investigated show similar changes in mean precipitation for the end of the twenty-first century, with increased precipitation projected between 10°S and 10°N, independent of the ability of the models to replicate ENSO variability. These results suggest separability between climate change and ENSO-like climate variability in the tropics.”

   • 

     shewonk Reply January 29, 2010 at 6:47 pm

     LL, this is fine but seriously, do you really feel competent to judge the literature on ENSO and global warming?

     I don’t. I can’t tell which papers are sound and which are weak and I can’t weigh the balance.

     If I could, I’d be a peer and would probably have a PhD in some climate science and years of research under my belt.

     You can put a paper in front of me and I can read it and get a sense of what it says and how much literature it cites to support its findings, but I can’t sort through the peer-reviewed papers and judge them against each other.

     That’s why we need some science organization to do this for policy makers and the layperson, who can’t hope to do it themselves.

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       Rattus Norvegicus Reply January 29, 2010 at 8:29 pm

       Given that this is just an abstract, and partially quoted at that, it is hard to tell. One thing is that this paper does not say anything about the extratropics, where precipitation is expected to be reduced. Hint, much of the Amazon rainforest lies outside of the 10N to 10S band examined in this paper.

     • 

       Layman Lurker Reply January 29, 2010 at 9:34 pm

       The only point of showing the reference was to support my first post.

       The jury is out on AGW caused ENSO variability. IPCC WG1 justifiably do not take a position on the matter. If you don’t believe me check it out in AR4 yourself:

       http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-5-4.html

       Basically the same thing the reference showed – the GCM runs are literally all over the board – more intense, less intense, no change, etc..

       So there is a conundrum. Since arguing AGW induced changes in ENSO is inconsistent with IPCC’s own published views, what is the foundation to make the “Amazongate” assertion?

       Susann, since much of what you are arguing depends on AGW caused ENSO severity, frequency, etc. – shouldn’t you be thinking about another “Mea Culpa”

       • 

         willard Reply January 30, 2010 at 1:34 am

         The Scholze et al 2006 paper can be found referenced in this section of the AR4, entitled *Forests and Woodlands*:

         http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch4s4-4-5.html

         Here follows the section entitled *Impact*. We note that the Rowell and Moore paper is not there, so all that is said there does not seem to rest on these two researchers. In my own humble opinion, I think we should quote it in full, for it’s time we show the document we’re seeing criticized:

         Projections for some forests currently limited by their minimum climatic requirements indicate gains from climate change (Figure 4.3, vegetation changes 1 and 2), but many may be impacted detrimentally (Figure 4.3, vegetation change 6), notably for strong warming and its concomitant effects on water availability (Bachelet et al., 2001, 2003; Bergengren et al., 2001; Ostendorf et al., 2001; Smith and Lazo, 2001; Xu and Yan, 2001; Arnell et al., 2002; Enquist, 2002; Iverson and Prasad, 2002; Lauenroth et al., 2004; Levy et al., 2004; Matsui et al., 2004; Izaurralde et al., 2005; Fuhrer et al., 2006; Lucht et al., 2006; Schaphoff et al., 2006; Scholze et al., 2006; cf. Figure 4.3a versus b, vegetation change 6). Productivity gains may result through three mechanisms: (i) CO2-fertilisation (although the magnitude of this effect remains uncertain in these long-lived systems, see Section 4.4.1); (ii) warming in cold climates, given concomitant precipitation increases to compensate for possibly increasing water vapour pressure deficits; and (iii) precipitation increases under water-limited conditions.

         There is growing evidence (see Chapter 5, Section 5.4.1.1) that several factors may moderate direct CO2 or climate-change effects on net ecosystem productivity in particular, namely nutrient dynamics (e.g., either enrichment or leaching resulting from N deposition), species composition, dynamic age structure effects, pollution and biotic interactions, particularly via soil organisms, (e.g., Karnosky et al., 2003; King et al., 2004b; Heath et al., 2005; Körner et al., 2005a; Section 4.4.1). Climate change impacts on forests will result not only through changes in mean climate, but also through changes in seasonal and diurnal rainfall and temperature patterns (as influenced by the hydrologically relevant surroundings of a forest stand, e.g., Zierl and Bugmann, 2005). Recently observed moderate climatic changes have induced forest productivity gains globally (reviewed in Boisvenue and Running, 2006) and possibly enhanced carbon sequestration, especially in tropical forests (Baker et al., 2004; Lewis et al., 2004a, 2004b; Malhi and Phillips, 2004; Phillips et al., 2004), where these are not reduced by water limitations (e.g., Boisvenue and Running, 2006) or offset by deforestation or novel fire regimes (Nepstad et al., 1999, 2004; Alencar et al., 2006) or by hotter and drier summers at mid- and high latitudes (Angert et al., 2005).

         Potential increases in drought conditions have been quantitatively projected for several regions (e.g., Amazon, Europe) during the critical growing phase, due to increasing summer temperatures and precipitation declines (e.g., Cox et al., 2004; Schaphoff et al., 2006; Scholze et al., 2006; Figure 4.3, vegetation change 6). Since all these responses potentially influence forest net ecosystem productivity (NEP), substantive biotic feedbacks may result, either through carbon releases or influences on regional climate, contributing to further major uncertainties (e.g., Betts et al., 2000; Peng and Apps, 2000; Bergengren et al., 2001; Semazzi and Song, 2001; Leemans et al., 2002; Körner, 2003c; Canadell et al., 2004; Cox et al., 2004; Gruber et al., 2004; Heath et al., 2005; Section 4.4.1). Effects of drought on forests include mortality, a potential reduction in resilience (e.g., Lloret et al., 2004; Hogg and Wein, 2005) and can cause major biotic feedbacks (e.g., Ciais et al., 2005; Box 4.1). However, these effects remain incompletely understood and vary from site to site (e.g., Reichstein et al., 2002; Betts et al., 2004). For example, drought impacts can be offset by fertile soils (Hanson and Weltzin, 2000), or if due to a heatwave, drought may even be accompanied by enhanced tree growth at cooler high elevation sites due to a longer growing season and enhanced photosynthetic activity (Jolly et al., 2005; Box 4.1).

         Drought conditions further interact with disturbances such as insects (Hanson and Weltzin, 2000; Fleming et al., 2002; Logan et al., 2003; Schlyter et al., 2006; Box 4.1) or fire (Flannigan et al., 2000). Tree-defoliating insects, especially in boreal forests, periodically cause substantial damage (e.g., Gitay et al., 2001, Box 5-10; Logan et al., 2003). Insect pests were found to be at least partly responsible for the decline and ultimate extirpation of stands at the southern margins of the range of their hosts, subjected to warmer and drier conditions (Volney and Fleming, 2000; see also Section 4.2.2). At the poleward ecotone (see Glossary), frosts and general low temperatures appear to limit insect outbreaks (Virtanen et al., 1996; Volney and Fleming, 2000); thus outbreaks currently constrained from northern ranges could become more frequent in the future (Carroll et al., 2004). If climate warms and this ecotone becomes exposed to more droughts, insect outbreaks will become a major factor (Logan et al., 2003; Gan, 2004). With A2 and B2 emissions scenarios downscaled to regional level in northern Europe, projected climate extremes by 2070-2100 will increase the susceptibility of Norway spruce to secondary damage through pests and pathogens, matched by an accelerated life cycle of spruce bark beetle populations (Schlyter et al., 2006).

         Climate change is known to alter the likelihood of increased wildfire sizes and frequencies (e.g., Stocks et al., 1998; Podur et al., 2002; Brown et al., 2004; Gillett et al., 2004), while also inducing stress on trees that indirectly exacerbate disturbances (Dale et al., 2000; Fleming et al., 2002; Schlyter et al., 2006). This suggests an increasing likelihood of more prevalent fire disturbances, as has recently been observed (Gillett et al., 2004; van der Werf et al., 2004; Westerling et al., 2006; Section 4.2.2).

         Considerable progress has been made since the TAR in understanding fire regimes and related processes (Kasischke and Stocks, 2000; Skinner et al., 2002; Stocks et al., 2002; Hicke et al., 2003; Podur et al., 2003; Gillett et al., 2004) enabling improved projections of future fire regimes (Flannigan et al., 2000; Li et al., 2000; de Groot et al., 2003; Brown et al., 2004; Fried et al., 2004). Some argue (e.g., Harden et al., 2000) that the role of fire regimes in the boreal region has previously been underestimated. About 10% of the 2002/2003 global carbon emission anomaly can be ascribed to Siberian fires by inverse modelling (van der Werf et al., 2004), as supported by remote sensing (Balzter et al., 2005). Climate changes including El Niño events alter fire regimes in fire-prone regions such as Australia (Hughes, 2003; Williams et al., 2004b; Allen Consulting Group, 2005), the Mediterranean region (e.g., Mouillot et al., 2002; see also Section 4.4.4), Indonesia and Alaska (Hess et al., 2001), but also introduce fire into regions where it was previously absent (e.g., Schumacher et al., 2006). Intensified fire regimes are likely to impact boreal forests at least as much as climate change itself (Flannigan et al., 2000), and may accelerate transitions, e.g., between taiga and tundra, through facilitating the invasion of pioneering trees and shrubs into tundra (Landhäusser and Wein, 1993; Johnstone and Chapin, 2006).

         Will forest expansions be realised as suggested by DGVMs (Figure 4.3)? Vegetation models project that forest might eventually replace between 11 and 50% of tundra with a doubling of atmospheric CO2 (White et al., 2000b; Harding et al., 2002; Kaplan et al., 2003; Callaghan et al., 2005; Figure 4.3, vegetation change 1). However, such transitions are likely to be moderated in reality by many processes not yet considered in the models (e.g., Gamache and Payette, 2005; see below). Other studies using a wide range of GCMs and forcing scenarios indicate that forests globally face the risk of major change (non-forested to forested and vice-versa within at least 10% of non-cultivated land area) in more than 40% of simulated scenarios if global mean warming remains below 2°C relative to pre-industrial, and in almost 90% of simulated scenarios if global mean warming exceeds 3°C over pre-industrial (Scholze et al., 2006). Those risks have been estimated as especially high for the boreal zone (44% and 88%, respectively) whereas they were estimated as smaller for tropical forests in Latin America (19% and 38%, respectively; see also Figure 4.3).

         One key process controlling such shifts is migration (e.g., Higgins and Harte, 2006). Estimates for migration rates of tree species from palaeoecological records are on average 200-300 m/yr, which is a rate significantly below that required in response to anticipated future climate change (³1 km/yr, Gitay et al., 2001, Box 5-2). However, considerable uncertainties remain:

         * although not completely quantified, many species can achieve rapid large-scale migrations (Reid’s paradox (see Glossary), e.g., Clark, 1998), but estimates at the low extreme imply a considerable range of lagged responses (Clark et al., 2001; e.g., lag 0-20 years, Tinner and Lotter, 2001; lag several millennia, Johnstone and Chapin, 2003);
         * recent genetic analysis (<100 m/yr, McLachlan et al., 2005) indicates that commonly inferred estimates from pollen have overestimated dispersal rates, explaining observed pollen records by multi-front recolonisation from low-density refugees (Pearson, 2006);
         * future landscapes will differ substantially from past climate change situations and landscape fragmentation creates major obstacles to migration (e.g., Collingham and Huntley, 2000);
         * processes moderating migration such as competition, herbivory and soil formation (land use – Vlassova, 2002; paludification – Crawford et al., 2003; herbivory – Cairns and Moen, 2004; Juday, 2005; pathogens – Moorcroft et al., 2006; Section 4.4.6);
         * tree species do not only respond to a changing climate by migration, but also by local adaptation, including genetic adaptation (Davis and Shaw, 2001; Davis et al., 2005).

         Modelling studies reconstructing past (e.g., Lischke et al., 2002) or projecting future (Malcolm et al., 2002b; Iverson et al., 2004; Neilson et al., 2005) dispersal all indicate that more realistic migration rates will result in lagged northward shifts of taiga (lag length 150-250 years, Chapin and Starfield, 1997; Skre et al., 2002). While shrubs and the tree line (see Glossary) were found to have advanced polewards in response to recent warming (Sturm et al., 2001; Lloyd, 2005; Tape et al., 2006; Chapter 1), the expected slow encroachment of taiga into tundra is confirmed by satellite data showing no expansion of boreal forest stands (Masek, 2001) indicating century-long time-lags for the forest limit (see Glossary) to move northward (Lloyd, 2005). All these findings suggest considerable uncertainties in how fast forests will shift northwards (e.g., Clark et al., 2003; Higgins et al., 2003; Chapin et al., 2004; Jasinski and Payette, 2005; McGuire et al., 2007) and in the resulting consequences for the climate system (discussed in Section 4.4.6). Lower rates for the majority of species are probably realistic, also because future conditions comprise both unprecedented climate characteristics, including rapid rates of change (Sections 4.2.1 and 4.4.11), and a combination of impediments to local adaptation and migration (with the exception of some generalists).

         Compared to the TAR (Gitay et al., 2001), the net global loss due to land-use change in forest cover appears to have slowed further (Stokstad, 2001; FAO, 2001), but in some tropical and sub-tropical regions, notably South-East Asia and similarly the Amazon (e.g., Nepstad et al., 1999), deforestation rates are still high (0.01-2.01%/yr, Lepers et al., 2005; Alcamo et al., 2006), while in some northern regions such as Siberia, degradation rates are increasing largely due to unsustainable logging (Lepers et al., 2005). Though uncertainties in rate estimates are considerable (e.g., FAO, 2001; Houghton, 2003b; Lepers et al., 2005), current trends in pressures (Nelson, 2005) will clearly lead to continued deforestation and degradation in critical areas (historically accumulated loss of 182-199 PgC – Canadell et al., 2004; expected releases in the 21st century of 40-100 PgC – Gruber et al., 2004; Shvidenko et al., 2005) with concomitant implications for biodiversity (Duraiappah et al., 2005) and other supporting services (Hassan et al., 2005). In most industrialised countries, forest areas are expected to increase (e.g., European forests by 2080 up to 6% for the SRES B2 scenario – Karjalainen et al., 2002; Sitch et al., 2005) partly due to intensified agricultural management and climate change.

         Although land-use changes may dominate impacts in some areas, climate change generally exacerbates biodiversity risks, especially in biodiversity hotspots and particularly for the first half of the 21st century (montane cloud forests – Foster, 2001; Hawaii – Benning et al., 2002; Costa Rica – Enquist, 2002; Amazonia – Miles, 2002; Australia – Williams et al., 2003). In tropical montane cloud forests, extinctions of amphibian species have been attributed to recent climate change (Pounds et al., 2006; see Section 4.4.7 and Table 4.1, No. 2). In a few exceptions, climate change may increase diversity locally or regionally (Kienast et al., 1998) but in most cases extinction risks are projected to increase.

         This is only a small portion of the AR4. Please note what it looks like in a blog layout. We’re not talking about a bodged school homework. It is a gigantic work, with a big wall of references. Not finding errors in this kind of report should be unlikely. Claiming one has read everything there would be preposterous.

         • 

           shewonk Reply January 30, 2010 at 10:02 am

           Thank you Willard.

           The denialists make it look as if the IPCC did no work and relied on a report by WWF activists for their section on impacts on Amazonia. Far from it but denialists don’t let the facts get in the way of good PR spin and disinformation, do they?

           Seriously, you read the IPCC reports and you read the skeptics’ apoplexy over a mistake and you realize what’s going on.

       • 

         shewonk Reply January 30, 2010 at 10:26 am

         Susann, since much of what you are arguing depends on AGW caused ENSO severity, frequency, etc. – shouldn’t you be thinking about another “Mea Culpa”

         Actually no. Let me explain. I was not arguing the merits of the evidence but the fact that there was evidence presented that supported the claims made in the IPCC section on impacts — evidence beyond the WWF report. A peer would have to decide on the merits of the evidence — I am unqualified to do that.

         I was arguing against the denialist claims that the IPCC based its conclusions on a single WWF report.

         • 

           Layman Lurker Reply January 30, 2010 at 2:01 pm

           I can see where you are comming from. I still believe there is too much ambiguity in the trasition from the original peer reviewed sources to the WG2 claim – to the point where one must question whether the claim was fair.

           Was the WG2 claim properly qualified given the context of the orignal peer reviewed sources? Did the claim depend on dubious attribution of increased ENSO drought effects to AGW?

           • 

             willard Reply January 30, 2010 at 6:46 pm

             Food for thought:

             http://mind.ofdan.ca/?p=2834#more-2834

             • 

               shewonk Reply January 30, 2010 at 9:07 pm

               I visited the link and checked it out. Here’s a quote:

               Dr Simon Lewis from Leeds University, who co-authored a paper on the Amazon in the journal Science, says the forest is surprisingly sensitive to drought.

               He told me: “The IPCC statement is basically correct but poorly written, and bizarrely referenced.

               “It is very well known that in Amazonia, tropical forests exist when there is more than about 1.5 metres of rain a year, below that the system tends to ‘flip’ to savannah.

               “Indeed, some leading models of future climate change impacts show a die-off of more than 40% Amazon forests, due to projected decreases in rainfall.

               “The most extreme die-back model predicted that a new type of drought should begin to impact Amazonia, and in 2005 it happened for the first time: a drought associated with Atlantic, not Pacific sea surface temperatures.

               “The effect on the forest was massive tree mortality, and the remaining Amazon forests changed from absorbing nearly two billion tonnes of CO2 from the atmosphere a year, to being a massive source of over three billion tonnes.”

               So, it appears that, unlike in the case of “Glaciergate”, the IPCC’s science may be right but its referencing wrong.

               Dr Lewis’s Science paper came too late for the Fourth Assessment Report’s deadline.

               But, he said: “They should have cited the papers by Peter Cox and colleagues on the modelling side, and a paper by Dan Nepstad on a massive drought exclusion experiment.”

               • 

                 shewonk Reply January 30, 2010 at 9:23 pm

                 Here’s a link to a study published in 2009 about the drought sensitivity of the Amazon, especially during the 2005 drought during which the Amazon switched from being a net carbon sink to a net carbon source.

                 Here’s a quote:

                 Amazon forests are a key but poorly understood component of the global carbon cycle. If, as anticipated, they dry this century, they might accelerate climate change through carbon losses and changed surface energy balances. We used records from multiple long-term monitoring plots across Amazonia to assess forest responses to the intense 2005 drought, a possible analog of future events. Affected forest lost biomass, reversing a large long-term carbon sink, with the greatest impacts observed where the dry season was unusually intense. Relative to pre-2005 conditions, forest subjected to a 100-millimeter increase in water deficit lost 5.3 megagrams of aboveground biomass of carbon per hectare. The drought had a total biomass carbon impact of 1.2 to 1.6 petagrams (1.2 x 1015 to 1.6 x 1015 grams). Amazon forests therefore appear vulnerable to increasing moisture stress, with the potential for large carbon losses to exert feedback on climate change.

     • 

       Rattus Norvegicus Reply January 29, 2010 at 9:56 pm

       I do agree with you that the science is far from settled on changes in ENSO variability. My point is that changes in precipitation outside of the tropics, primarily decreases in the mid latitudes, are not addressed in this paper.

       The evidence for extratropical decreases is much stronger than changes in ENSO variability.

       • 

         Layman Lurker Reply January 29, 2010 at 10:02 pm

         Hey RN how’s it going. I was actually responding to Susann. WRT to extratropics vs tropics, could you quantify the proportion of Amazon rain forest which falls within 10N and 10S? Also, does IPCC have any reference to precip in extratropics? If not what other sources do you have?

         • 

           Rattus Norvegicus Reply January 29, 2010 at 11:35 pm

           Looking at the maps, I would have to say that I had a mistaken impression about the southern extent of the forest. It appears that very little of the Amazon drainage lies outside of this band.

3. 

   willard Reply February 5, 2010 at 10:25 am

   More gatekeeping :

   http://bit.ly/9jborF

4. 

   willard Reply March 21, 2010 at 7:01 am

   New developments about the Amazon file, not unsurprisingly considering the development rate of the Amazon forest:

   http://rabett.blogspot.com/2010/03/there-have-been-number-of-developments.html