Global_JJ Warming_NN1 Global_JJ warming_NN1 involves_VVZ an_AT1 unprecedented_JJ speeding_VVG up_RP of_IO the_AT rate_NN1 of_IO change_NN1 in_II natural_JJ processes_NN2 ,_, which_DDQ now_RT converges_VVZ with_IW the_AT (_( previously_RR much_RR faster_RRR )_) rate_NN1 of_IO change_NN1 in_II human_JJ societies_NN2 ,_, leading_VVG to_II a_AT1 crisis_NN1 of_IO adaptation_NN1 ._. 
Most_DAT authoritative_JJ scientific_JJ bodies_NN2 predict_VV0 that_CST on_II present_JJ trends_NN2 a_AT1 point_NN1 of_IO no_AT return_NN1 could_VM come_VVI within_II ten_MC years_NNT2 ,_, and_CC that_CST the_AT world_NN1 needs_VVZ to_TO cut_VVI emissions_NN2 by_II 50_MC percent_NNU by_II mid_JJ twenty-first_MD century_NNT1 ._. 
It_PPH1 was_VBDZ natural_JJ scientists_NN2 who_PNQS first_MD discovered_VVD and_CC raised_VVD global_JJ warming_NN1 as_II a_AT1 political_JJ problem_NN1 ._. 
This_DD1 makes_VVZ many_DA2 of_IO the_AT global_JJ warming_NN1 concerns_VVZ unique_JJ ._. 
"_" Science_NN1 becomes_VVZ the_AT author_NN1 of_IO issues_NN2 that_CST dominate_VV0 the_AT political_JJ agenda_NN1 and_CC become_VV0 the_AT sources_NN2 of_IO political_JJ conflict_NN1 "_" ._. 
Perhaps_RR for_IF this_DD1 reason_NN1 ,_, many_DA2 social_JJ scientists_NN2 ,_, particularly_RR sociologists_NN2 ,_, wary_JJ of_IO trusting_VVG the_AT truth_NN1 claims_NN2 of_IO natural_JJ science_NN1 but_CCB knowing_VVG themselves_PPX2 lacking_VVG the_AT expertise_NN1 to_TO judge_VVI their_APPGE validity_NN1 ,_, have_VH0 avoided_VVN saying_VVG much_RR about_II global_JJ warming_NN1 and_CC its_APPGE possible_JJ consequences_NN2 ._. 
Even_RR sociologists_NN2 such_II21 as_II22 Ulrich_NP1 Beck_NP1 and_CC Anthony_NP1 Giddens_NP1 ,_, who_PNQS see_VV0 "_" risk_NN1 "_" as_II a_AT1 key_JJ attribute_NN1 of_IO advanced_JJ modernity_NN1 ,_, have_VH0 said_VVN little_RR about_II climate_NN1 change_NN1 ._. 
For_IF practical_JJ purposes_NN2 ,_, it_PPH1 can_VM no_RR21 longer_RR22 be_VBI assumed_VVN that_DD1 nature_NN1 is_VBZ a_AT1 stable_JJ ,_, well_RR understood_VVN ,_, background_NN1 constant_NN1 and_CC thus_RR social_JJ scientists_NN2 do_VD0 not_XX need_VVI direct_JJ knowledge_NN1 about_II its_APPGE changes_NN2 ._. 
Any_DD discussion_NN1 of_IO likely_JJ social_JJ ,_, economic_JJ ,_, and_CC political_JJ futures_NN2 will_VM have_VHI to_TO heed_VVI what_DDQ natural_JJ scientists_NN2 say_VV0 about_II the_AT likely_JJ impacts_NN2 of_IO climate_NN1 change_NN1 ._. 
While_CS originally_RR eccentric_JJ ,_, global_JJ warming_NN1 was_VBDZ placed_VVN firmly_RR on_II the_AT agenda_NN1 in_II 1985_MC ,_, at_II a_AT1 conference_NN1 in_II Austria_NP1 of_IO eighty-nine_MC climate_NN1 researchers_NN2 participating_VVG as_CSA individuals_NN2 from_II twenty-three_MC countries_NN2 ._. 
The_AT researchers_NN2 forecast_VV0 substantial_JJ warming_NN1 ,_, unambiguously_RR attributable_JJ to_II human_JJ activities_NN2 ._. 
Since_CS that_DD1 conference_NN1 the_AT researchers_NN2 '_GE position_NN1 has_VHZ guided_VVN targeted_VVD empirical_JJ research_NN1 ,_, leading_VVG to_II supporting_VVG (_( and_CC increasingly_RR dire_JJ )_) evidence_NN1 ,_, resolving_VVG anomalies_NN2 and_CC winning_VVG near_II unanimous_JJ peer_NN1 endorsement_NN1 ._. 
Skeptics_NN2 have_VH0 been_VBN confounded_VVN and_CC reduced_VVN to_II a_AT1 handful_NN1 ,_, some_DD discredited_JJ by_II revelations_NN2 of_IO dubious_JJ funding_NN1 from_II fossil_NN1 fuel_NN1 industries_NN2 ._. 
Just_RR before_II the_AT end_NN1 of_IO the_AT twentieth_MD century_NNT1 ,_, American_JJ researchers_NN2 released_VVN ice-thickness_JJ data_NN ,_, gathered_VVN by_II nuclear_JJ submarines_NN2 ._. 
The_AT data_NN showed_VVD that_CST over_II the_AT previous_JJ forty_MC years_NNT2 the_AT ice_NN1 depth_NN1 in_II all_DB regions_NN2 of_IO the_AT Arctic_JJ Ocean_NN1 had_VHD declined_VVN by_II approximately_RR 40_MC percent_NNU ._. 
Five_MC yearly_JJ aerial_NN1 photographs_NN2 show_VV0 the_AT ice_NN1 cover_NN1 on_II the_AT Arctic_JJ Ocean_NN1 at_II a_AT1 record_NN1 low_NN1 ,_, with_IW a_AT1 loss_NN1 of_IO 50_MC cubic_JJ kilometers_NNU2 annually_RR and_CC glacier_NN1 retreat_NN1 doubling_VVG to_II 12_MC kilometers_NNU2 a_AT1 year_NNT1 ._. 
In_II September_NPM1 2005_MC the_AT National_JJ Aeronautics_NN1 and_CC Space_NN1 Administration_NN1 (_( NASA_NP1 )_) doubled_VVD its_APPGE estimates_NN2 of_IO the_AT volume_NN1 of_IO melted_JJ fresh_JJ water_NN1 flowing_VVG into_II the_AT North_ND1 Atlantic_NP1 ,_, reducing_VVG salinity_NN1 and_CC thus_RR potentially_RR threatening_VVG the_AT conveyor_NN1 that_CST drives_VVZ the_AT Gulf_NP1 Stream_NN1 ._. 
Temperate_JJ mussels_NN2 have_VH0 been_VBN found_VVN in_II Arctic_JJ waters_NN2 ,_, and_CC news_NN1 broadcasts_NN2 in_II 2005_MC and_CC 2006_MC have_VH0 repeatedly_RR shown_VVN scenes_NN2 of_IO Inuit_NN1 and_CC polar_JJ bears_NN2 (_( recently_RR listed_VVN as_CSA endangered_VVN )_) cut_VV0 off_RP from_II their_APPGE hunting_NN1 grounds_NN2 as_II the_AT ice_NN1 bridges_NN2 melt_VV0 ._. 
In_II 2001_MC the_AT Intergovernmental_JJ Panel_NN1 on_II Climate_NN1 Change_NN1 (_( IPCC_NP1 )_) ,_, the_AT United_JJ Nation_NN1 's_GE scientific_JJ panel_NN1 on_II climate_NN1 change_NN1 ,_, had_VHD predicted_VVN that_CST Antarctica_NP1 would_VM not_XX contribute_VVI significantly_RR to_II sea_NN1 level_NN1 rise_VV0 this_DD1 century_NNT1 ._. 
The_AT massive_JJ west_ND1 Antarctic_JJ ice_NN1 sheet_NN1 was_VBDZ assumed_VVN to_TO be_VBI stable_JJ ._. 
However_RR ,_, in_II June_NPM1 2005_MC a_AT1 British_JJ Antarctic_JJ survey_NN1 reported_VVD measurements_NN2 of_IO the_AT glaciers_NN2 on_II this_DD1 ice_NN1 sheet_NN1 shrinking_NN1 ._. 
In_II October_NPM1 2005_MC glaciologists_NN2 reported_VVD that_CST the_AT edges_NN2 of_IO the_AT Antarctic_JJ ice_NN1 sheets_NN2 were_VBDR crumbling_VVG at_II an_AT1 unprecedented_JJ rate_NN1 and_CC ,_, in_II one_MC1 area_NN1 ,_, glaciers_NN2 were_VBDR discharging_VVG ice_NN1 three_MC times_NNT2 faster_RRR than_CSN a_AT1 decade_NNT1 earlier_RRR ._. 
In_II 2005_MC an_AT1 eight-year_JJ European_JJ study_NN1 drilling_VVG Antarctic_JJ ice_NN1 cores_NN2 to_TO measure_VVI the_AT past_JJ composition_NN1 of_IO the_AT atmosphere_NN1 reported_VVD that_CST CO2_FO levels_NN2 were_VBDR at_RR21 least_RR22 30_MC percent_NNU higher_JJR than_CSN at_II any_DD time_NNT1 in_II the_AT last_MD 65,000_MC years_NNT2 ._. 
The_AT speed_NN1 of_IO the_AT rise_NN1 in_II CO2_FO was_VBDZ unprecedented_JJ ,_, from_II 280_MC parts_NN2 per_II million_NNO (_( ppm_NNU )_) before_II the_AT Industrial_JJ Revolution_NN1 to_II 388_MC ppm_NNU in_II 2006_MC ._. 
Early_RR in_II 2007_MC the_AT Norwegian_JJ Polar_JJ Institute_NN1 reported_VVD acceleration_NN1 to_II a_AT1 new_JJ level_NN1 of_IO 390_MC ppm_NNU ._. 
In_II January_NPM1 2006_MC a_AT1 British_JJ Antarctic_JJ survey_NN1 ,_, analyzing_VVG CO2_FO in_II crevasse_NN1 ice_NN1 in_II the_AT Antarctic_JJ Peninsula_NN1 ,_, found_VVD levels_NN2 of_IO CO2_FO higher_RRR than_CSN at_II any_DD time_NNT1 in_II the_AT previous_JJ 800,000_MC years_NNT2 ._. 
In_II April_NPM1 2005_MC a_AT1 NASA_NP1 Goddard_NP1 Institute_NN1 oceanic_JJ study_NN1 reported_VVD that_CST the_AT earth_NN1 was_VBDZ holding_VVG on_RP to_II more_RGR solar_JJ energy_NN1 than_CSN it_PPH1 was_VBDZ emitting_VVG into_II space_NN1 ._. 
The_AT Institute_NN1 's_GE director_NN1 said_VVD :_: "_" This_DD1 energy_NN1 imbalance_NN1 is_VBZ the_AT 'smoking_JJ gun'_NN1 that_CST we_PPIS2 have_VH0 been_VBN looking_VVG for_IF "_" (_( Columbia_NP1 2005_MC )_) ._. 
The_AT second_MD IPCC_NP1 report_NN1 in_II 1996_MC had_VHD predicted_VVN a_AT1 maximum_JJ temperature_NN1 rise_NN1 of_IO 3.5_MC degrees_NN2 Fahrenheit_VV0 by_II the_AT end_NN1 of_IO the_AT twenty-first_MD century_NNT1 ._. 
The_AT third_MD report_NN1 ,_, in_II 2001_MC ,_, predicted_VVD a_AT1 maximum_JJ rise_NN1 of_IO 5.8_MC degrees_NN2 Fahrenheit_VV0 by_II the_AT end_NN1 of_IO the_AT twenty-first_MD century_NNT1 ._. 
In_II October_NPM1 2006_MC Austrian_JJ glaciologists_NN2 reported_VVN in_II Geophysical_JJ Research_NN1 Letters_NN2 (_( Kaser_NP1 et_RA21 al._RA22 )_) that_CST almost_RR all_DB the_AT world_NN1 's_GE glaciers_NN2 had_VHD been_VBN shrinking_VVG since_II the_AT 1940s_MC2 ,_, and_CC the_AT shrinking_JJ rate_NN1 had_VHD increased_VVN since_II 2001_MC ._. 
None_PN of_IO the_AT glaciers_NN2 (_( contrary_II21 to_II22 skeptics_NN2 )_) was_VBDZ growing_VVG ._. 
Melting_VVG glaciers_NN2 could_VM pose_VVI threats_NN2 to_II the_AT water_NN1 supply_NN1 of_IO major_JJ South_NP1 American_JJ cities_NN2 and_CC is_VBZ already_RR manifest_VV0 in_II the_AT appearance_NN1 of_IO many_DA2 new_JJ lakes_NN2 in_II Bhutan_NP1 ._. 
In_II January_NPM1 2007_MC global_JJ average_JJ land_NN1 and_CC sea_NN1 temperatures_NN2 were_VBDR the_AT highest_JJT ever_RR recorded_VVN for_IF this_DD1 month_NNT1 ;_; in_II February_NPM1 2007_MC the_AT IPCC_NP1 Fourth_MD Report_NN1 ,_, expressing_VVG greater_JJR certainty_NN1 and_CC worse_JJR fears_NN2 than_CSN the_AT previous_JJ one_PN1 ,_, made_VVD headlines_NN2 around_II the_AT world_NN1 ._. 
In_II 1995_MC few_DA2 scientists_NN2 believed_VVD the_AT effects_NN2 of_IO global_JJ warming_NN1 were_VBDR already_RR manifest_VV0 ,_, but_CCB by_II 2005_MC few_DA2 scientists_NN2 doubted_VVD it_PPH1 and_CC in_II 2007_MC few_DA2 politicians_NN2 were_VBDR willing_JJ to_TO appear_VVI skeptical_JJ ._. 
Although_CS rising_VVG temperatures_NN2 ;_; melting_VVG tundra_NN1 ,_, ice_NN1 and_CC glaciers_NN2 ;_; droughts_NN2 ;_; extreme_JJ storms_NN2 ;_; stressed_JJ coral_NN1 reefs_NN2 ;_; changing_VVG geographical_JJ range_NN1 of_IO plants_NN2 ,_, animals_NN2 ,_, and_CC diseases_NN2 ;_; and_CC sinking_VVG atolls_NN2 may_VM conceivably_RR all_DB be_VBI results_NN2 of_IO many_DA2 temporary_JJ climate_NN1 variations_NN2 ,_, their_APPGE cumulative_JJ impact_NN1 is_VBZ hard_JJ to_TO refute_VVI ._. 
The_AT science_NN1 of_IO global_JJ warming_NN1 has_VHZ progressed_VVN through_II tackling_VVG anomalies_NN2 cited_VVN by_II skeptics_NN2 ._. 
Critics_NN2 of_IO global_JJ warming_NN1 made_VVD attempts_NN2 to_TO discredit_VVI the_AT methodology_NN1 of_IO climatologist_NN1 Michael_NP1 Mann_NP1 's_GE famous_JJ "_" Hockey_NN1 stick_NN1 "_" graph_NN1 (_( first_MD published_VVN in_II Nature_NN1 in_II 1998_MC )_) ._. 
Mann_NP1 's_GE graph_NN1 showed_VVD average_JJ global_JJ temperatures_NN2 over_II the_AT last_MD 1,000_MC years_NNT2 ,_, with_IW little_DA1 variation_NN1 for_IF the_AT first_MD 900_MC and_CC a_AT1 sharp_JJ rise_NN1 in_II the_AT last_MD century_NNT1 ._. 
After_CS more_DAR than_CSN a_AT1 dozen_NNO replication_NN1 studies_NN2 ,_, some_DD using_VVG different_JJ statistical_JJ techniques_NN2 and_CC different_JJ combinations_NN2 of_IO proxy_NN1 records_NN2 (_( indirect_JJ measures_NN2 of_IO past_JJ temperatures_NN2 such_II21 as_II22 ice_NN1 cores_NN2 or_CC tree_NN1 rings_VVZ )_) ,_, Mann_NP1 's_GE results_NN2 were_VBDR vindicated_VVN ._. 
A_AT1 report_NN1 in_II 2006_MC by_II the_AT U.S._NP1 National_JJ Academy_NN1 of_IO Sciences_NN2 ,_, National_JJ Research_NN1 Council_NN1 ,_, supported_VVD much_DA1 of_IO Mann_NP1 's_GE image_NN1 of_IO global_JJ warming_NN1 history_NN1 ._. 
"_" There_EX is_VBZ sufficient_JJ evidence_NN1 from_II the_AT tree_NN1 rings_NN2 ,_, boreholes_NN2 ,_, retreating_VVG glaciers_NN2 and_CC other_JJ 'proxies_NN2 '_GE of_IO past_JJ surface_NN1 temperatures_NN2 to_TO say_VVI with_IW a_AT1 high_JJ level_NN1 of_IO confidence_NN1 that_CST the_AT last_MD few_DA2 decades_NNT2 of_IO the_AT twentieth_MD century_NNT1 were_VBDR warmer_JJR than_CSN any_DD comparable_JJ period_NN1 for_IF the_AT last_MD 400_MC years_NNT2 ._. "_" 
For_IF periods_NN2 before_II 1600_MC ,_, the_AT 2006_MC report_NN1 found_VVD there_EX was_VBDZ not_XX enough_RR reliable_JJ data_NN to_TO be_VBI sure_JJ but_CCB the_AT committee_NN1 found_VVD the_AT "_" Mann_NP1 team_NN1 's_GE conclusion_NN1 that_CST warming_VVG in_II the_AT last_MD few_DA2 decades_NNT2 of_IO the_AT twentieth_MD century_NNT1 was_VBDZ unprecedented_JJ over_II the_AT last_MD 1,000_MC years_NNT2 to_TO be_VBI plausible_JJ "_" (_( National_JJ Academy_NN1 of_IO Science_NN1 press_NN1 release_NN1 2006_MC )_) ._. 
Measurements_NN2 from_II satellites_NN2 and_CC balloons_NN2 in_II the_AT lower_JJR troposphere_NN1 have_VH0 until_II recently_RR indicated_VVN cooling_VVG ,_, which_DDQ contradicted_VVD measurements_NN2 from_II the_AT surface_NN1 and_CC the_AT upper_JJ troposphere_NN1 ._. 
In_II August_NPM1 2005_MC a_AT1 publication_NN1 in_II Science_NN1 of_IO the_AT findings_NN2 of_IO three_MC independent_JJ studies_NN2 described_VVD their_APPGE measurements_NN2 as_II "_" nails_NN2 in_II the_AT coffin_NN1 "_" of_IO the_AT skeptics_NN2 '_GE case_NN1 ._. 
These_DD2 showed_VVD that_CST faulty_JJ data_NN ,_, which_DDQ failed_VVD to_TO allow_VVI for_IF satellite_NN1 drift_NN1 ,_, lay_VVD behind_II the_AT apparent_JJ anomaly_NN1 ._. 
Another_DD1 anomaly_NN1 was_VBDZ that_DD1 observed_JJ temperature_NN1 rises_NN2 were_VBDR in_II fact_NN1 less_RRR than_CSN the_AT modelling_NN1 of_IO CO2_FO impacts_NN2 predicted_VVD ._. 
This_DD1 is_VBZ now_RT explained_VVN by_II evidence_NN1 on_II the_AT temporary_JJ masking_NN1 properties_NN2 of_IO aerosols_NN2 ,_, from_II rising_VVG pollution_NN1 and_CC a_AT1 cyclical_JJ upward_JJ swing_NN1 of_IO volcanic_JJ eruptions_NN2 since_II 1960_MC ._. 
Critics_NN2 of_IO global_JJ warming_NN1 have_VH0 been_VBN disarmed_VVN and_CC discredited_VVN ._. 
Media_NN investigations_NN2 and_CC social_JJ research_NN1 have_VH0 increasingly_RR highlighted_VVN the_AT industry_NN1 funding_NN1 of_IO skeptics_NN2 and_CC their_APPGE think_NN1 tanks_NN2 ,_, and_CC the_AT political_JJ pressures_NN2 on_II government_NN1 scientists_NN2 to_TO keep_VVI silent_JJ ._. 
Estimates_NN2 of_IO the_AT catastrophic_JJ costs_NN2 of_IO action_NN1 on_II emissions_NN2 have_VH0 also_RR been_VBN contradicted_VVN most_RGT dramatically_RR by_II the_AT British_JJ Stern_JJ Report_NN1 in_II October_NPM1 2006_MC ._. 
Many_DA2 companies_NN2 have_VH0 been_VBN abandoning_VVG the_AT skeptical_JJ business_NN1 coalitions_NN2 ._. 
The_AT Australian_JJ Business_NN1 Round_II Table_NN1 on_II Climate_NN1 Change_NN1 estimated_VVN in_II 2005_MC that_CST the_AT cost_NN1 to_TO gross_VVI domestic_JJ product_NN1 of_IO strong_JJ early_JJ action_NN1 would_VM be_VBI minimal_JJ and_CC would_VM create_VVI jobs_NN2 ._. 
In_II May_NPM1 2001_MC sixteen_MC of_IO the_AT world_NN1 's_GE national_JJ academies_NN2 of_IO science_NN1 issued_VVD a_AT1 statement_NN1 ,_, confirming_VVG that_CST the_AT IPCC_NP1 should_VM be_VBI seen_VVN as_II the_AT world_NN1 's_GE most_RGT reliable_JJ source_NN1 of_IO scientific_JJ information_NN1 on_II climate_NN1 change_NN1 ,_, endorsing_VVG its_APPGE conclusions_NN2 and_CC stating_VVG that_CST doubts_NN2 about_II the_AT conclusions_NN2 were_VBDR not_XX justified_VVN ._. 
In_II July_NPM1 2005_MC the_AT heads_NN2 of_IO eleven_MC influential_JJ national_JJ science_NN1 academies_NN2 (_( from_II Brazil_NP1 ,_, Canada_NP1 ,_, China_NP1 ,_, France_NP1 ,_, Germany_NP1 ,_, India_NP1 ,_, Italy_NP1 ,_, Japan_NP1 ,_, Russia_NP1 ,_, the_AT United_NP1 Kingdom_NP1 ,_, and_CC the_AT United_NP1 States_NP1 )_) wrote_VVD to_II the_AT G8_FO leaders_NN2 warning_VVG that_DD1 global_JJ climate_NN1 change_NN1 was_VBDZ "_" a_AT1 clear_JJ and_CC increasing_JJ threat_NN1 "_" and_CC that_CST they_PPHS2 must_VM act_VVI immediately_RR ._. 
They_PPHS2 outlined_VVD strong_JJ and_CC long-term_JJ evidence_NN1 "_" from_II direct_JJ measurements_NN2 of_IO rising_VVG surface_NN1 air_NN1 temperatures_NN2 and_CC subsurface_NN1 ocean_NN1 temperatures_NN2 and_CC from_II phenomena_NN2 such_II21 as_II22 increases_NN2 in_II average_JJ global_JJ sea_NN1 levels_NN2 ,_, retreating_VVG glaciers_NN2 and_CC changes_NN2 to_II many_DA2 physical_JJ and_CC biological_JJ systems_NN2 "_" (_( Joint_JJ Science_NN1 Academies_NN2 Statement_NN1 2005_MC )_) ._. 
There_EX are_VBR many_DA2 unknowns_NN2 regarding_II global_JJ warming_NN1 ,_, particularly_RR those_DD2 dependent_JJ on_II human_JJ choices_NN2 ;_; yet_RR the_AT consequences_NN2 for_IF society_NN1 of_IO either_RR inadequate_JJ action_NN1 or_CC of_IO any_DD effective_JJ responses_NN2 (_( through_II reduced_JJ consumption_NN1 or_CC enforced_JJ and_CC subsidized_VVD technological_JJ change_NN1 )_) will_VM be_VBI huge_JJ ._. 
It_PPH1 is_VBZ ,_, for_REX21 example_REX22 ,_, unlikely_JJ that_CST the_AT practices_NN2 and_CC values_NN2 of_IO free_JJ markets_NN2 ,_, individualism_NN1 ,_, diversity_NN1 ,_, and_CC choice_NN1 will_VM not_XX be_VBI significantly_RR modified_VVN either_RR by_II economic_JJ and_CC political_JJ breakdowns_NN2 or_CC alternatively_RR by_II the_AT radical_JJ measures_NN2 needed_VVN to_TO preempt_VVI them_PPHO2 ._. 
Kyoto_NP1 targets_NN2 are_VBR at_RR21 best_RR22 a_AT1 useful_JJ first_MD step_NN1 ._. 
However_RR ,_, even_RR these_DD2 targets_NN2 ,_, which_DDQ seek_VV0 to_TO peg_VVI back_RP emissions_NN2 to_II 1990_MC levels_NN2 by_II 2010_MC ,_, are_VBR unlikely_JJ to_TO be_VBI met_VVN ._. 
World_NN1 CO2_FO emissions_NN2 in_II 2004_MC continued_VVD to_TO rise_VVI in_II all_DB regions_NN2 of_IO the_AT world_NN1 ,_, by_II another_DD1 4.5_MC percent_NNU ,_, to_II a_AT1 level_NN1 26_MC percent_NNU higher_JJR than_CSN in_II 1990_MC ._. 
A_AT1 rise_NN1 of_IO over_RG 2_MC degrees_NN2 is_VBZ considered_VVN inevitable_JJ if_CS CO2_FO concentrations_NN2 pass_VV0 400_MC ppm_NNU ._. 
At_II current_JJ growing_JJ emission_NN1 rates_NN2 ,_, the_AT concentration_NN1 would_VM reach_VVI 700_MC ppm_NNU by_II the_AT end_NN1 of_IO the_AT twenty-first_MD century_NNT1 ._. 
The_AT continuing_JJ industrialization_NN1 of_IO China_NP1 ,_, recently_RR joined_VVN by_II India_NP1 ,_, points_VVZ to_II the_AT possibility_NN1 of_IO even_RR faster_JJR rises_NN2 than_CSN these_DD2 projections_NN2 indicate_VV0 ._. 
If_CS unpredictable_JJ ,_, amplifying_VVG feedback_NN1 loops_NN2 are_VBR triggered_VVN ,_, improbable_JJ catastrophes_NN2 become_VV0 more_RGR likely_JJ ._. 
The_AT Gulf_NP1 Stream_NN1 flow_NN1 could_VM be_VBI halted_VVN ,_, freezing_JJ Britain_NP1 and_CC Northern_JJ Europe_NP1 ._. 
Droughts_NN2 could_VM wipe_VVI out_RP the_AT agriculture_NN1 of_IO Africa_NP1 and_CC Australia_NP1 ,_, as_II31 well_II32 as_II33 Asia_NP1 ,_, where_CS millions_NNO2 depend_VV0 on_II Himalayan_JJ melt_NN1 water_NN1 and_CC monsoon_NN1 rains_VVZ ._. 
If_CS the_AT ice_NN1 caps_NN2 melt_VV0 completely_RR over_II the_AT next_MD centuries_NNT2 ,_, seas_NN2 could_VM rise_VVI by_II 7_MC meters_NN2 ,_, devastating_VVG all_DB coastal_JJ cities_NN2 ._. 
Will_VM the_AT human_JJ response_NN1 to_II widespread_JJ ecological_JJ disasters_NN2 give_VV0 rise_NN1 to_II solidarity_NN1 and_CC collective_JJ action_NN1 ,_, such_II21 as_II22 the_AT aid_NN1 that_CST came_VVD after_II the_AT 2004_MC Asian_JJ Tsunami_NN1 or_CC to_II social_JJ breakdowns_NN2 ,_, as_CSA seen_VVN in_II New_NP1 Orleans_NP1 after_II 2005_MC 's_GE Hurricane_NN1 Katrina_NP1 and_CC in_II the_AT Rwandan_NP1 genocide_NN1 ?_? 
Social_JJ and_CC technical_JJ changes_NN2 with_IW the_AT scale_NN1 and_CC speed_NN1 required_VVN are_VBR not_XX unprecedented_JJ ._. 
The_AT displacement_NN1 of_IO horsepower_NN1 by_II automobiles_NN2 ,_, for_REX21 example_REX22 ,_, was_VBDZ meteoric_JJ ._. 
Production_NN1 of_IO vehicles_NN2 in_II the_AT United_NP1 States_NP1 increased_VVD from_II 8,000_MC in_II 1900_MC to_II nearly_RR a_AT1 million_NNO by_II 1912_MC ._. 
Substantial_JJ regulation_NN1 or_CC differential_JJ taxation_NN1 and_CC subsidies_NN2 would_VM be_VBI indispensable_JJ to_TO overcome_VVI short_JJ term_NN1 profit_NN1 motives_NN2 and_CC free_JJ riding_NN1 dilemmas_NN2 ._. 
Gains_NN2 in_II auto_NN1 efficiency_NN1 in_II the_AT 1980s_MC2 ,_, for_REX21 example_REX22 ,_, were_VBDR rapidly_RR reversed_VVN by_II a_AT1 new_JJ fashion_NN1 for_IF sport_NN1 utility_NN1 vehicles_NN2 ._. 
The_AT debates_NN2 that_CST have_VH0 emerged_VVN in_II the_AT early_JJ twenty-first_MD century_NNT1 have_VH0 been_VBN related_VVN to_II responses_NN2 ,_, with_IW different_JJ winners_NN2 and_CC losers_NN2 ,_, costs_NN2 ,_, benefits_NN2 ,_, dangers_NN2 ,_, and_CC time_NNT1 scales_NN2 for_IF each_DD1 response_NN1 ._. 
Advocates_NN2 of_IO reduced_JJ energy_NN1 consumption_NN1 or_CC increased_JJ efficiency_NN1 ,_, or_CC energy_NN1 generation_NN1 by_II solar_JJ ,_, wind_NN1 ,_, tidal_JJ ,_, hydro_NN1 ,_, biomass_NN1 ,_, geothermal_JJ ,_, nuclear_JJ ,_, or_CC clean_JJ coal_NN1 and_CC geo-sequestration_NN1 ,_, argue_VV0 often_RR cacophonously_RR ._. 
It_PPH1 will_VM be_VBI essential_JJ for_IF social_JJ and_CC natural_JJ scientists_NN2 to_TO learn_VVI to_TO cooperate_VVI in_II understanding_NN1 and_CC preempting_VVG the_AT potentially_RR catastrophic_JJ collision_NN1 of_IO nature_NN1 and_CC society_NN1 ._. 
In_BCL21 order_BCL22 to_TO accomplish_VVI this_DD1 ,_, market_VV0 mechanisms_NN2 ;_; technological_JJ innovation_NN1 ;_; international_JJ ,_, national_JJ ,_, and_CC local_JJ regulations_NN2 ;_; and_CC cultural_JJ change_NN1 will_VM all_DB be_VBI needed_VVN ._. 
Agents_NN2 of_IO change_NN1 include_VV0 governments_NN2 ,_, nongovernmental_JJ organizations_NN2 ,_, and_CC public_NN1 opinion_NN1 ,_, but_CCB the_AT most_RGT likely_JJ front-runner_NN1 might_VM be_VBI sectors_NN2 of_IO capital_NN1 seeking_VVG profit_NN1 by_II retooling_VVG the_AT energy_NN1 and_CC transport_NN1 systems_NN2 ,_, while_CS able_JK to_TO mobilize_VVI political_JJ enforcement_NN1 ._. 
