Experimental Wood products C tab (HWP storage + Avoided Carbon)

src/App.jsx

@@ -8,6 +8,7 @@ import LandisStratified from "./LandisStratified.jsx";
 import LandownerYields from "./LandownerYields.jsx";
 import FaustmannRotation from "./FaustmannRotation.jsx";
 import AOIReport from "./AOIReport.jsx";
+import HWPStorage from "./HWPStorage.jsx";
 import { findFeature, agbAtAge, polygonCentroid, polygonAreaM2, pointInGeometry } from "./geo.js";
 
 const BASE = import.meta.env.BASE_URL; // "./" -> resolves relative to the page
@@ -263,6 +264,7 @@ export default function App(){
   const [landis,setLandis] = useState(null);
   const [landowner,setLandowner] = useState(null);
   const [faustmann,setFaustmann] = useState(null);
+  const [hwp,setHwp] = useState(null); // experimental HWP storage layer
   // v1.3 map/AOI tools
   const [ecoOn,setEcoOn] = useState(false);
   const [ecoGeo,setEcoGeo] = useState(null);
@@ -285,6 +287,7 @@ export default function App(){
     j("api/landis_stratified.json").then(setLandis).catch(()=>{});
     j("api/landowner_yields.json").then(setLandowner).catch(()=>{});
     j("api/faustmann_rotation.json").then(setFaustmann).catch(()=>{});
+    j("api/hwp_storage.json").then(setHwp).catch(()=>{});
     geo.features.forEach(ft=>{ const st=ft.properties.state; const c=s[st];
       ft.properties.engines = c ? c.engines : 0;
       ft.properties.hasSeries = (c && c.has_series) ? 1 : 0;
@@ -837,12 +840,14 @@ export default function App(){
           <div className="tabs">
             {[["engines","Engine compare"],["rd","RD trend"],["divergence","Engine spread"],
               ["stumpage","Stumpage"],["landis","LANDIS stratified"],
-              ["landowner","Landowner yields"],["faustmann","Faustmann rotation"]].map(([k,lbl])=>{
+              ["landowner","Landowner yields"],["faustmann","Faustmann rotation"],
+              ["hwp","Wood products C"]].map(([k,lbl])=>{
               const disabled = (k==="divergence" && !divergence)
                 || (k==="stumpage" && !(stumpage && stumpage.series && stumpage.series[sel]))
                 || (k==="landis" && !(landis && landis[sel]))
                 || (k==="landowner" && !(landowner && landowner[sel]))
                 || (k==="faustmann" && !(faustmann && faustmann[sel]))
+                || (k==="hwp" && !(hwp && hwp.states && hwp.states[sel]))
                 || ((k==="engines"||k==="rd") && !series);
               return <button key={k} className={"tab"+(tab===k?" on":"")} disabled={disabled}
                 onClick={()=>setTab(k)} title={disabled?"no data for this state":lbl}>{lbl}</button>;
@@ -856,6 +861,7 @@ export default function App(){
           {tab==="landis" && <LandisStratified data={landis} state={sel}/>}
           {tab==="landowner" && <LandownerYields data={landowner} state={sel}/>}
           {tab==="faustmann" && <FaustmannRotation data={faustmann} state={sel}/>}
+          {tab==="hwp" && <HWPStorage data={hwp} state={sel}/>}
           {(tab==="engines"||tab==="rd") && (<>
           {LANDIS_STATES.includes(sel) && (
             <div className="controls" style={{margin:"0 4px 8px"}}>

src/HWPStorage.jsx

@@ -0,0 +1,65 @@
+// Harvested wood products (HWP) carbon storage tab. Experimental layer.
+// Source: api/hwp_storage.json (WPsCS-exact pool model, Wei 2022 service lives,
+// driven by the PERSEUS hybrid harvest). Shows the in-use / landfill / charcoal
+// stored-carbon pools and the cumulative Avoided Carbon (substitution) line,
+// per state and management scenario. Reported separately from forest carbon
+// per the FACT (Forestry Analytics for Carbon Tracking) taxonomy.
+import { useState, useEffect } from "react";
+import MiniChart from "./MiniChart.jsx";
+
+const SCEN_ORDER = ["managed (harvest)", "managed (intensive)",
+  "managed (conservation)", "reserve (no harvest)"];
+const POOL = [
+  { key: "total",    label: "HWP total",        color: "#d7301f" },
+  { key: "solid",    label: "In-use solidwood", color: "#fe9929" },
+  { key: "paper",    label: "In-use paper",     color: "#41ab5d" },
+  { key: "landfill", label: "Landfill",         color: "#6baed6" },
+  { key: "charcoal", label: "Charcoal",         color: "#8d6e63" },
+];
+
+export default function HWPStorage({ data, state }){
+  const stData = data && data.states && data.states[state];
+  const scens = stData
+    ? SCEN_ORDER.filter(s => stData[s]) : [];
+  const [scen, setScen] = useState(scens[0] || "managed (harvest)");
+  useEffect(() => { if(scens.length && !scens.includes(scen)) setScen(scens[0]); }, [state]);
+
+  if(!data || !data.states) return <div className="empty">HWP storage data not loaded.</div>;
+  if(!stData) return <div className="empty">No HWP storage for {state}.</div>;
+
+  const rows = stData[scen] || [];
+  const line = key => rows.map(r => [r.year, null, r[key], null]);
+  const poolSeries = POOL.map(p => ({ label: p.label, color: p.color, pts: line(p.key) }));
+  const avoidSeries = [{ label: "Avoided (substitution)", color: "#9467bd", pts: line("avoided") }];
+
+  const last = rows[rows.length - 1] || {};
+  return (
+    <div>
+      <div className="controls" style={{marginTop:0}}>
+        <select value={scen} onChange={e=>setScen(e.target.value)} title="Management scenario">
+          {scens.map(s => <option key={s} value={s}>{s}</option>)}
+        </select>
+        <span style={{color:"var(--mut)",fontSize:12,alignSelf:"center"}}>stored carbon (Tg C)</span>
+      </div>
+      <div className="chartcard" style={{padding:"6px 8px"}}>
+        <MiniChart series={poolSeries} unit="Tg C" xlabel="Year"/>
+      </div>
+      <div className="lgd" style={{marginTop:8}}>
+        {POOL.map(p => <span key={p.key}><i style={{background:p.color,width:14,height:3}}/>{p.label}</span>)}
+      </div>
+      <div className="chartcard" style={{padding:"6px 8px",marginTop:10}}>
+        <MiniChart series={avoidSeries} unit="Tg C (cumulative)" xlabel="Year"/>
+      </div>
+      <div className="note">
+        <b>Stored carbon</b> in harvested wood products under <b>{scen}</b> for {state}:
+        in-use solidwood (building/exterior/home), paper, landfill, and charcoal pools,
+        from a WPsCS-style first-order-decay model (Wei 2022 service lives) driven by the
+        PERSEUS hybrid harvest. At {last.year}: HWP total {last.total?.toFixed(1)} Tg C.
+        The lower panel is <b>Avoided Carbon</b> (substitution of wood for non-wood
+        materials, cumulative, displacement factor 1.2) reported separately per the FACT
+        taxonomy, never added to stored-carbon totals. <i>Experimental layer; parameters
+        (regional product allocation, recycling) not yet finalized. Data: api/hwp_storage.json.</i>
+      </div>
+    </div>
+  );
+}